re: Two slots.
You could turn it off, try it out. It certainly won't break anything. If you have a D: drive, there might be one on there also. I run windows with 1Gb and no page file. Mostly I use Linux and that's without a swap partition, similar to the page file.
Your bottleneck could be the hard drive also. Are you using the SATA port on your motherboard or is your harddrive PATA.
Here's a question. Have you ever used system restore? If not, kill that pig.