Windows 2KPro Freezes browzing the web

Hi,
I have a multiple boot machine. When I boot into 2000 connect to the internet using Verizon DSL (WinPPPoverEthernet) invariablely my surfing is cut short because the screen freezes. The only way to recover is to restart the machine. Sometimes it will happen right away, sometimes I could be on for an hour. Any ideas?

Joe