Now that's odd badboy...
Right off the top of my head (even though it's mostly empty)...
You have an oddball amount of system RAM...I'm willing to bet it's mixed memory chips with different timings...sometimes an issue, sometimes not.
You paging file is huge...a lot of stuff running in the background there...and Skuzzy will tell you the same thing.
And AGP graphics card and you're running the video resolution this high: Current Mode: 1920 x 1200 (32 bit) (60Hz)
That's higher than what the monitor max is: Monitor Max Res: 1600,1200
Try dropping that to 1440x900 for starters...you might be able to adjust up a little from there but you're pushing the processor on your graphics card to it's full level which takes away from it's performance...think of it like your system processor...if it's maxed out, things run slower.
Sound card driver is very out dated...Date and Size: 2/18/2004 16:51:08...it's gonna be tough finding a newer one but I did it yesterday by googling it...just be careful of where you get it from.
You could try just lowering you video card resolution to start with then find out what's making such a huge paging file and getting rid of the un necessary junk... then proceed from there. I'm assuming you disable your anti-virus program before you start playing too.