Its a pc and yes, I can open the Gothic ini in notepad. are there changes I should make there?

Go in there and under [Sound} heading change these values:
SoundVolume=0 (it will say something between 0 and 1 most likely)
MusicEnabled=0
SoundEnabled=0
Making all three of those zeroes should disable all sound. Then exit and save the ini file, and try running the game. If it runs, then that tells us its definitely a sound issue.
I'm leaning more towards a sound issue because I'm sure the Nvidea 6600 with latest drivers SHOULDN'T be a problem, though it's still a possibility. It could also be a memory issue as well, particularly if you have virus scanners running in the background. After disabling sound in the INI file, my next troubleshooting step would be to try disabling any virus scan software running and see if that helps.
I apologize I'm not more of a help, as I was hoping someone more knowledgable might've chimed in by now, but I'll keep trying. I know I've been frustrated by games before. Nascar 2003 frustrated me for awhile, and Civ IV gave me fits at first too. I eventually got them running, but I feel your pain (to quote a former President).
Anyway, if someone smarter than I helps before I get back, that would be great. In the meantime, I'll keep checking back and I'll definitely keep wishing you the best, because man I am LOVING this game. After loving Gothic 2, then hating Gothic 3, it was SO NICE to get back into a loving feeling all over again. THIS GAME IS GREAT ! ! ! !

Ok, it may not be a sound problem then. The odds are about a billion to 1 that I'm going to help you, so I keep posting in the hopes that by keeping this thread at the top someone smarter will join in and help.
In the meantime, try this. Leaving sound disabled, look in the INI file and make the following lines equal the following values if they don't already. These appear under [Video] which is just above sound IIRC.
zvidResFullscreenX=1024
zvidResFullscreenY=768
zvidResFullscreenBPP=32
Save the file, and try running it again. If that doesn't work, then try changing the following (LEAVING ALL OTHER CHANGES YOU'VE MADE ALONE TO THE CHANGED VALUES)
zstartupwindowed=1
If nothing works after all of this, I would try uninstalling, then re-installing in it's entirety. This will reset the INI file back to it's original defaults and may also clear out other unknown issues we haven't thought of. If things still don't work, well, let's brainstorm after that.
AND PLEASE OTHER SMARTER PEOPLE READING THIS JOIN IN AT ANY TIME OK :D

OFG tried all your suggestions still not working. I unstalled it and am downloading the game again. Will try a fresh install tomorow. thanks.

Same issues with new install, game won't load. (sad face).

OK, I'm grasping at staws here, but the next two things I would try are these.
First of all, (I can't imagine this working since it's supposed to be for XP but it's worth a shot), try running it under the compatibility tab as if under Windows 2000. To do that, you right click on the Gothic Icon, and click on Properties. Then, a box will come up with three tabs at the top, General, Shortcut (the default), and Compatibility. Click on the Compatibility tab. Then, click the empty box where it says "Run this Program in Compatibility Mode for" and that will open up the dropdown box where you can then select Windows 2000. Then click Apply, then click OK and try running it as if under Windows 2000. It's a long shot, but worth a try. If as I suspect it doesn't help, don't forget to back into Properties and changing it back to running under XP by clearing that box that you clicked above.
The other next step I would suggest is opening up the Task Manager and under Processes start eliminating everything under your name (leave the SYSTEM, LOCAL SERVICE, and NETWORK SERVICE processes running for now). I would elminate everything under your name EXCEPT explorer.exe EDIT: Also taskmgr.exe (I say your name because that's how it's listed in my PC, might be different in yours). . But try eliminating all of those processes except those two under your name and then try running the game. Don't worry, these processes will all return the next time you restart Windows.
Those would be my next two tries. I'm still hoping someone smarter will come along and help though

OldFatGuy....I've been at this now for the last 2 1/2 hours, following your instructions about stopping different processes. At one point the game actually loaded and I played for a few minutes. I even saved the game. I decided to exit the game and try again, no luck this time. The game does start to load sometimes but I get this message....
C: failed to initialize sound, MSS reported: Wave Out Open() failed
I went back into Gothic ini. and set all sound settings to 0. Still can't get it to run

OK, it's looking more and more like a sound or memory issue to me. Let's start from the sound issue.
I'm not sure what type of speakers you have, and I now can't remember what the "default" setting is for Gothic, but I have a complete surround sound system with 5 satellites and a subwoofer. In game you have three choices IIRC, headphones, surround sound, and 4 speakers. I have experienced problems in the past where an in-game setting that was different from the Windows setting created problems. More on that if we need to at a later time.
The MSS error means it was a Miles Sound System error, and I have my sound settings set to EAX 2. IIRC, EAX 2 is thought to be more unstable than Miles, which is why Miles is the default. However, for grins, lets change yours. And since you can't get in game to do it, we'll have to try using the INI file. I've looked at mine and the three lines that I found that I think might change it are found very near the bottom of the INI file. So, try going into the INI file and see if any or all of these three lines have different values in your INI and if so, change them to the values below. (Take a pencil and write down the original values in case we need to change them back) The three lines are these:

soundProviderIndex=2
soundSampleRateIndex=1
soundSpeakerIndex=2
Give this a go a see if it helps. And again for those reading, I'm no computer expert at all, if anyone with more computer knowledge is reading this I hope you'll try and help. I know what it's like to purchase a game that runs fine for everyone else but simply won't on my computer. It's frustrating, and in my experience, it's usually fixable IF YOU KNOW where to look. My problem is I don't know enough to know where to look always. I'm going on memory of issues I've had in the past.

Hey OldF(riend), did as you said still no luck. I'm about ready to throw in the towel on this one. Words can"t express my gratitude to you for all your help in trying to get MY problem resolved. Its not like I haven't played games on this computer before. i just finished up Oblivion, Divine Divinity, Beyond Divinity and am currently playing Pool Of Radiance. This game should be no problem for my system. I just wish GOG support would chime in here. Thanks for all your help.....

I hope you don't give up because this is such a GREAT game. I still think its some sort of sound system, and the reason the INI changes aren't helping is probably because that Phiranha Bytes intro requires sound and I'm betting the INI changes only affect IN-GAME sound. Plus, it worked once, remember??? Anyways, if you've still got the stomach for trying things, I found these specific answers to the error message you reported at the World of Gothic website. It may be worth a try??? Anyways, good luck to you, I know I am in heaven all over again playing this thing. It is so IMMERSIVE and fun it's just great.
Anywho, here's the suggestion's I found:
I get the Error-message "C: failed to initialize sound, MSS reported: waveOutOpen() failed." whenever I try to run Gothic I.
Solution(s):
1) Software such as TotalRecorder turn the DirectSound-Hardware access off. When you have such software installed, follow the following procedure:
Rightclick the audioystem on the right of the systemtray. Choose "Change audio settings". Click on the "Audio" tab. And set the top "audio rendition" to the Soundcard, and click apply.
2)Set the hardware acceleration in the DirectX diagnosis program the soundcardsettings to the maximum. To open the program go to start -> run/execute and enter "dxdiag" (without quotationmarks) and hit enter or click ok. After the program has gathered the system information, go to the "Sound" tab.
If you can here is what I would do. I would revert the INI back to default. (If you need to do this but can't remember the changes you've made, simply reinstall the game). Then, I would restart my computer, go into Task Manager, and close down all of the processes under your name EXCEPT explorer.exe and taskmgr.ext. Then, I would do the two suggestions above, regarding the sound card and DirectX sound settings.
If doing all of that (reinstalling which resets INI, stopping all processes except the 2, and making the 2 changes above) it still doesn't work, then I might be more inclined to give up, but even then the fact you got it to work for a few minutes tells me it WILL work on your machine. We just need to find exactly what is causing the conflict. It's a tedious troubleshooting step, and I still believe there are some out there that have had the same or similar issues and would be in better position to help than I have been. I am still hoping someone will be able to help better than I. Either way, good luck to you.

OldFatGuy, when I go to Task Manager/processes and End the first three svchost.exe from the top of the list, Gothic works. (everytime). I can live with this work around. Thank you soo much for not giving up on me. Got to get back to my game....... ; )

Nice one, fat and grey, now everyone's happy. I'm running from swamp-sharks at the moment.

Wow, you must be ahead of me already ! ! ! I have a question for you (and for anyone else whose played the GOG version)
Was Cavelorn at the site Fingers said he would be for you??? Ever??? I have still NEVER encountered Cavelorn anywhere in my game, and I wonder if this a bug in the GOG version.

Just an update:
I downloaded a program called Process Explorer. This let me view what each svchost.exe was linked to. The one that was preventing Gothic from loading is called
HP NETWORK DEVICE SUPPORT [HPSLPSVC]. I end this process and the game runs great. Thanks again for all your help..