artoodeeto9 on the StarWars.com forums
has detailed how he got Windows X-Wing and TIE Fighter working in Windows Vista 64-bit. He did it by dual-booting with Windows XP Media Center Edition (I'm assuming regular Windows XP 32-bit will do, as well), installing the games through that OS, then booting into Vista and copying (or moving) the files from the XP Media Center volume to the Vista volume and running "Cwagle the Jedi's" compatibility fix. artoodeeto9 reports that the training missions perform very well in Vista 64-bit.
I believe XvT/BoP and XWA can be "installed" in 64-bit Vista using a similar procedure, but there may be Registry keys that have to be ported over for those games, as well (Admiral Alistair already documented this procedure for XWA on the XWA Upgrade forums, but he was speaking about 64-bit XP.).