Let me introduce you to eduke32, the latest and greatest source port for Duke Nukem 3D to modern platforms such as windows, mac OSX and linux. It has unbelievable graphics enhancements, countless bug fixes, and other modern features. Here's the homepage:
http://eduke32.com/ and although you can get it from that site, you'll be guaranteed to have the cutting edge latest version from here:
http://dukeworld.duk...ke32/synthesis/ (eduke32 is updated frequently).
Also check out the official High Resolution Pack, which replaces all of Duke's classic textures with hi res, modern artwork, and replaces many of the flat, pixelated 2D sprites with 3D models. You can get it here:
http://hrp.duke4.net/download.php although actually I think even that is getting old now. If you're truely passionate about Duke and always want to have the latest graphics, install this program which will constantly update your HRP to keep it up to scratch:
http://forums.duke4....?showtopic=2251
Also you might want to use DeeperThought's DukePlus mod, which also has some con-related bug fixes, and adds many modern gameplay features and graphics enhancements which weren't in the original game.
http://deeperthought.dukertcm.com/dp/
So to actually answer your questions:
1) To get the game running, all you need is eduke32.exe, and the DUKE3D.GRP from your Duke Nukem 3D disk in the same folder, then double click on eduke32.
2) I'd suggest running it on the desktop, since if you want the latest graphics, the desktop is more likely to have a dedicated graphics card.
3) XP, Vista, 7, it makes no difference, eduke32 is awesome and works on everything. If you can't get it to work, or are interested in using the included
polymer renderer post back in this thread and we'll help you