lol...the commit charge peak isn't set by the computer...it's just telling you the highest your commit charge total has ever gotten. Commit charge or page file is sort of like fake memory on your harddrive and as such, is much slower. When your computer runs out of normal memory running large programs (such as photoshop) it puts some of it into this page file. When something on the page file is needed, it has to be swaped with something in memory and then accessed (hence the horrible slowing down of the computer). In order to speed your computer up while running these large programs you need more memory...how much memory are you running now?
(btw...your commit charge total can never be more than your commit charge peak...cus the peak is just telling you the highest your total has ever gotten since the last restart....so as total passes peak....the value of peak will change to match total. make sence?)
/edit if the comp in your sig is the one you've having issues with...then I have no idea why there's slowing down cus you have plenty of memory (1 gig for those of you with sigs off). I can't see why it's slowing down...