Why do you have so many partitions? Well, some people say assigning the paging file to a partition besides your primary boot one is the best option, but I beg to differ. If it's still on the same harddrive that you're using, it's still having to jump back and forth between the swap and loading whatever you're loading.
Now then, the typical rule of thumb for swap files is to set them to around 1.5x the amount of RAM you have. So something like 768M would probably be fine. And that's both largest and smallest size. If you let windows manage the size, or have a range set, this could slow windows down(or so I hear)
Your BEST bet for performace is simply to get more physical RAM.