Well, so far you haven't told us anything about why Tribunal and Bloodmoon won't work, or even what you mean by "won't work" but I can take a good guess that you're having the common problems that Vista creates.
Check the http://www.gamesas.com/index.php?/topic/781497-vistawindows-7-problems/ for some solutions to all the common problems.
You'll probably want to change Install Location, and make sure you're running the game as Admin. (which is different than just being logged-in as Admin)
Well if he has a crappy graphics card, then he wouldnt be using vista or 7
Many laptops (including those that use Vista or W7) have integrated cards that just aren't that great for Morrowind. Some even create graphical bugs like the ones described here.