I'm changing my HDD (500GB to 1TB) and I have a little question.
Just copying the folder to the new HDD is enough to play it or I have to download the installer again and reinstall it? And what about the savegames, just copying them is enough?

Thanks :)

If the installation paths are the same, most of the games should work just fine when you copied them over, I guess DosBox games will work without problem, I remember I always had problems with EA games, they always needed a register value to work, so I had to reinstall them, but those olders ones that work on DosBox shouldn't have this problem.
As for the savegames, almost every game works just fine if you copy them (or the profile), I think I had some problems with Unreal and Unreal Tournament though.

As fexen said, DOSBOX games should be fine, as they have nowhere to hide things. A lot of windows games use at least a few registry keys, so they will probably either not work, or be unstable.

EDIT: However if you're keen on keeping your save games etc. What you could do is re-install, then copy old folder over the top of it. That is more likely to work.

EDIT 2: My post is on the assumption you're changing your OS.

If the disk you're upgrading contains the OS, I'd suggest using a partitioning or disk copy tool so that you don't have to reinstall. Check this thread for some recommendations.

If the OS is on another disk, then copying in Windows should work.

I'll go the opposite way to everybody (as usual): if you are permanently switching to a new HDD, the best thing you could do is to "refresh" your OS and install your applications/games anew. Sure, it will take more time, but it's the most secure way to get a perfect, issue-free result.

As for saved games, every game is different so you should learn how to copy the save files on the new HDD. Personally, I won't bother with that anyway: the only "valuable" stuff I have on saved games is for Diablo II, every other thing is completely disposable and utterly useless to me....

Well, now I have Windows XP and I'm going to change to W7, the game that I want to save my saves is The Witcher. In "My Documents" folder there is a The Witcher/saves folder, copying it will be enough?

And about copying the game, should it cause problems with the Windows Registry?

Ok, thank you to all who answered, I'll see how I manage to copy all :)

I think you should reinstall The Witcher, I had all in-game text dissapear for me when I run it from a hard disk, which The Witcher was installed before I installed new system on my system disk. Your saves should be fine, I guess.

This is one of the issues I have with GOG. They don't actually fix the mess about where save games are saved. Some of them are under My Games in some directory, and some are in the install directory.

But, yeah, definitely snag the entire My Documents folder, worst case, you just have to delete it later. But definitely go through it at some specified time later, and delete it. You don't want to have dozens of copies of things you don't really need anymore.

Hedwards looks at his disk drive in shame with all the duplicates he's made that way over the years.

a sure fire way to get everything is to copy your games install folders... then copy your entire "documents" folder type %userdocuments% to find it in the RUN dialogue

then reinstall everything... you can alos use a program called "FreeFileSync" Its a little crazy and you'll need to play around a bit to get it down. But it works awesome! http://sourceforge.net/projects/freefilesync/

bottom line and the hard way... research save location on all games then reinstall and import saves, this will give you the best performance and remember not to fill up the 1TB to full... the more data you toss on the slower it will be.

Thanks to all, tomorrow or the next I'll install w7 and I tell you about how it went :)

Double-post to say that copying The Witcher didn't work, I had to reinstall it and copying the saves didn't give any problem :D

I can't verify it at the moment, but I think that it needed some registry keys and the extra episodes were stored somewhere inside the all users folder for some reason that I really can't even begin to understand. Yet another thing to mlink away from my SSD...