I have no experience with the intel graphics card under vista. In general I wouldn't run SL on any intel graphics cards, but your friend might try one of the unofficial sl viewers.
Nicholaz ciewer - Have had some nice results on this viewer with intel graphics cards:
http://nicholaz-beresford.blogspot.com/Cool viewer - Pretty "cool" with a lot of nice features - Eth had some crashes with this viewer though, so not sure if it will do the same with your friends computer:
http://my.opera.com/boylane/blog/Imprudence viewer - They are making an 100% opensource SL viewer. Its a really nice project with a lot of promish, but still in an early development, so there are some bugs:
http://imprudenceviewer.org