My Computer Hang while loading

I have a problem where 'My Computer' sometimes hangs when I double-click it. The window pops up, but remains blank and hangs there. My mouse is still active at this point. I thought at first that it happened only when I was online or using multimedia apps, but it happens occasionally right after startup. I usually have to restart the computer. Here's my system : P3 533 Mhz, Asus P3V4X Motherboard, 10GB HD (7GB have been used up), 64MB 100 Mhz SDRAM, ATI 32MB Rage Fury, Soundblaster Live Value, A-0pen 56K software Modem, and a Sony 48x CD-Rom. The things I have running on my system are Windows 98 SE, Norton Anti-Virus (I have System Works, but I disabled the Crash Guard when I realized it was doing more harm than good), MSN Messenger, and Disk Detector (I disabled that but the problem still persists). I also run Scandisk and Defrag regularily as well. This 'hang' happened to me a few nights ago, and when I hit Ctrl-Alt-Delete to end the task I received a 'blue screen of death' with this error message : 'Terminating Thread due to a stack overflow problem. A Vxd, possibly recently installed, has consumed too much stack space. Increase the setting of 'MinSPs' in SYSTEM.INI or remove recently installed VxD's. There are currently 5 SPs allocated.' This is the first time that this has appeared. The only things I've installed recently are a few games, and the message doesn't make sense to me. If someone could help me I'd really appreciate it.