First, you should never disable VM under OS X. Doing this would cause you more headaches then it is probably worth. Instead, focus on improving your VM's performance, as well as OS X's, and you will live a long and happy day.
1.) Use window compression. This will save you a great deal of RAM, and cut down on disk thrashing.
There is a thread within this site's Tips & Tricks section which desribes how to do it. Takes all of three minutes, and works wonderfully.
2.) Keep your disk optimized. Every time I feel OS X slowing down, I know that I must do three things. First, run through and delete or move any extranuos large files you may have galavanting around your startup partition. Second, boot into single-user mode, run fsck. Third, get a copy of Norton 6.0 and run speed disk, wiping blank space.
3.)And yes, you can move your swap file. It's located under /var/vm. Follow one of the hundreds of tutorials around the net, and you should be fine.