video capture no longer works

Video capture used to work, now doesn't. Not sure if something broke or if it's just an issue with settings. I had been successfully capturing via the USB port using a number of different video programs, and was recently trying to obtain better image by changing capture settings using VirtualDub Video when one of the settings caused the PC to bluescreen. I've since had mixed results when going into "capture" mode on various programs:
1. VirtualDub - When selecting WDM Capture Device: "Error-Cannot connect to desired capture driver"
2. ULead Video Studio - When going into capture mode, program crashes, exits, & writes error log. "Exception number: c0000005 (access violation)"
3. Moviestar 5 - In Capture mode, "Video Device" selection pulldown contains no devices.
These all worked before.
"Settings/Control Panel/Device Manager" says everything is enabled & functioning properly.
System info:
Laptop - Dell Latitude C640
OS - W2K
Display device - Mobility Radeon 7500
Display driver - ATI, 8/12/2003, ver.6.14.10.6378

This isn't what caused it but have you tried updating the device drivers from ATI:
https://support.ati.com/ics/support/...ge&folderID=27