My DVD drive makes my computer unusable

I have been experiencing slow program installs for a long time on my computer, but never really noticed it because I didn't use it for much that required the drive running at the same time as any other media. Recently, that has changed--I would like to watch movies and I'm replaying some older games that (for whatever reason) spins the drive now and again during cutscenes. Plus, it just takes forever for things to burn or install.

Symptoms:
During DVD Playback, video slows down and audio is at a constant stutter.
During Video Game cutscenes, everything is fine until the read light comes on, then the video slows and and there is audio stutter.
If I'm playing Pandora, life is great. Start a DVD, no problems on the FBI warning and seemingly any audio-less shots. As soon as that read light comes on (constant during the main movie), Pandora's audio stutters, which means it's a system global kind of thing.

Comp specs:
MB - Abit AB 9 Pro
2 G Dual Channel RAM
hDD - WDC WD2500KS on SATA1
Toshiba SD-R5002 DVD/RW as the Slave on my Primary IDE channel. I only have one IDE port and have tried the drive as both the Master and the Slave. I have also uninstalled and reinstalled my Primary IDE channel.

I have one Unknown Device that I can't chase down since the last time I wiped my drive. I do not know if this was happening before my recent formatting.

This problem is making me hate my life.