flickenmaste: I am thinking of buying either fallout 1 or 2(which ever is better)
Do they run well on windows 7 or do I have to install extra stuff?
You will probably not have many problems. One easy way to avoid issues is to install to a directory OTHER than Program Files, as this directory has extra security protections in Windows 7 and can cause problems with older games. If you buy the GOG version of the game, just hit the "options" button on the installer to change the install path.
Another common problem has to do with modern graphics cards, and gives some funky rainbow colors. Apparently this usually only happens with Fallout 2, and can usually be fixed with a few quick steps. Check out the following thread for details:
http://www.gog.com/en/forum/fallout_series/fallout_2_colors_problem/page1 As for which game to pick, there is much debate over whether Fallout 1 or 2 is better. I think it's safe to say that they're both great games, and I'd recommend playing them in order so you experience them as the creators intended. While they don't have much of a connection plot-wise, it's still interesting to see the events of Fallout 2 after you've played Fallout 1 and know the backstory.
Disclaimer: I personally prefer Fallout 1, but I enjoyed Fallout 2 quite a bit also.