I have the same problem as hls1966 except that my internet discrepancy is less predicable (anywhere from 2mins to 6 hours)
I don't know what vmware is so I'm not sure I have it, but I've only installed the windows updates, drivers, firefox/flash pluggin, and steam.
I just installed the driver off:
Linksys by Cisco - WUSB100 Support
and it has let me be on for 57mins with no trouble yet, but I'm not sure if it has fixed it.
I will post if I have the problem again, but any suggestions of what could be wrong would be greatly appreciated.