I've been having this problem for the better part of six months....
I finally got the google search term correct and I finally found a solution!
Basically, whenever I tried to get a properties sheet in IIS under XP, it'd
either not work or crash.
The fix is described here (excerpt from the VS2005 readme):
http://weblogs.asp.net/datagridgirl/archive/2004/04/01/105836.aspx
I hope this is of use to someone.
It's bound to be of use to someone. If you're experiencing this you can
search yourself silly.