It looks like Descent 1 GOG comes preconfigured to run at 640x480. Some LCD monitors have trouble displaying lower-than-their-minimum resolutions. My friend's, for example, can't go below 800x600, and goes wonky when it tries.
I don't have any experience with the Windows API, but would there be a way for the installer to retrieve that minimum value and insert it into the DOSBox conf file? Or some other way to auto-detect an appropriate res?
This is probably a problem for other games too.

I had a similar problem when I tried to run Descent. The main problem was when I booted it up the screen went pure black and I could not see the game even though I could hear it. This happened because your monitor most likely cannot handle that resolution because it is to small.
To fix it I found that Dos-Box opens a game at a set resolution. So I went to this link http://www.dosbox.com/wiki/Dosbox.conf. This gives you a list of commands for the configuration file and how to change them. I opened Dosbox.conf file with notepad and changed this line 'fullresolution = original' to 'fullresolution= 1280 x 1024' or whatever resolution you want. Close the file and run the game. Should fix the problem. It did for me.

Yes, I'm aware of the problem and how to fix it. I'm asking/suggesting a way for this to be automated by the installer so users less savvy than you aren't out in the cold. :)

I figured out how to get it to run in a higher resolution completely and with anti-aliasing(somewhat). Use the opengl option expesially in vista. If you use direct3d, it screws with dreamscene. Also use the advmam3x scaler. This makes it look a lot better on a large monitor.

I second the suggestion for D1X - Rebirth project; the game runs like a charm for me with it.

For reference,

Setting as below worked for me:

fullscreen=true
fulldouble=true
fullresolution=1280 x 400

My downloaded version will not allow editing of the dosbox.conf file--every time I try to save it a prompt comes up saying access is denied. Any thoughts?

That sounds like an issue with permissions in Windows, not the file you're trying to edit. One option is to run your editor of choice with elevated privileges to edit the file. You might want to start a new thread if you continue to have issues since this one has been marked solved.

I can't figure this out. How exactly do I open the configuration file?? Also, it's really slow. The shareware version worked fine, but this isn't looking too great.

I'd suggest using DXX-Rebirth: http://www.dxx-rebirth.com/

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