Slow machine

WoW has been working extremely slowly for me, lately. I noticed this yesterday, the first time I played since coming home from vacation. On my vacation, I downloaded bittorrent. That is the only thing I changed as far as I know. Now, all of a sudden, WoW is running like I'm in Orgrimmar the whole time. I don't know what I might have done since this has never happend before. I did 2 virus scanse, 2 spyware searches (using AVG's anti-virus software and Lavasoft's Adaware), defragged my machine, packet sniffed my machine, and checked the processes multiple times. Everything seems okay to me. Virus scanning and spyware scanning turned up negative. Defragging didn't seem to do anything for me. All packets sent and recieved over a period of 3 minutes were expected -- meaning there isn't anything utilizing my network without me knowing. I don't know if the processes are correct, but it doesn't look like anything is running that shouldn't be. Furthermore, even Yahoo pool gets extremely sluggish when I'm running 2 instances of firefox or if I get an invitation or something. My latency is <100 on WoW. I don't know what could possibly be going wrong. Checking the WoW server forums, there doesn't seem to be any problem with burning legion, and i've never heard anyone having problems with WoW and Bittorrent being on the same machine (mind you, bittorrent is always off when I play WoW or pool). After uninstalling bittorrent, my machine was still slow. The only thing I've changed since then is I've got bittorrent and the new patch. I don't know anything else that could be effecting the performance of my machine.

Any help would be appreciated. I really don't want to have to format this thing.

If this helps, here's my process list: