I'm having the same problem, virtualized Win 7 and love it in all respects except this one. I get an error loading VS (can't find .vssettings, errors when I try and create same) and then the "failed to start monitoring changes" error when trying to run an ASP.NET website (any, not just the admin tool).
The only article I found online about this problem is this one: http://alextafoya.com/post/2009/08/19/Make-Visual-Studio-work-with-VMWare-Fusion-shares.aspx#comment
But when I try and follow the instructions, the first step (registry change) doesn't affect anything and the second change I can't do b/c I don't have the SDk installed, and get a "not a valid win32 application" error when I try and install it.
Very frustrating.