I have two DVD drives on my PC. One is a WDC ROM the other is a pioneer burner. Just recently I haven't been able to use either of these drives because as soon as I load a disc into either of them and try to access them the PC freezes instantly. Nothing works except the manual reset button. If I try to open a program like DVD shrink, same thing the PC freezes, however DVD decrypter is able to access the drives and rip and burn DVDs no problems. I have checked the drivers and they are the most up to date available. I tried uninstalling and reinstalling to no avail. My operating system is windows XP SP3. I use an INTEL dual core 3.something GH processor with 2G of RAM.

For starters you might try a System Restore to a point prior to your problem:

start > All Programs > Accessories > System Tools > System Restore