Yes. FS2 runs on XP, and is known to run on Vista and 7 as long as there is not too much RAM (that is, 2GB or more). Or was it 4GB? Nah, I'm sure it was 2GB. If you do have 2GB or more RAM and want to play FS2, I'd direct you towards FreeSpace Open ( http://www.hard-light.net/wiki/index.php/Getting_started#The_FreeSpace_Source_Code_Project
), which, in short, is a modified version of the FSO game engine. Among all sorts of cool things, it can also deal with large amounts of RAM without issues. And it makes it possible to enable significant graphical improvements made by the FreeSpace fan community at Hard Light Productions.
If you have questions about FreeSpace Open, it would probably be better for you to visit http://www.hard-light.net/forums
/ , as there are more active people there, ready to answer any and all questions.