Font pack causes operating system problems?

I've been an Apple user for about 9 months now, and my PowerBook had run flawlessly for the duration. However, earlier today, I made the mistake of installing a font pack that took up almost 1.5 GB of memory. As I was adding it to Font Book, my computer behaved strangely, slowing down considerably and even focing me to restart manually due to a lock up. When I returned to my computer several hours later, it was working fine barring a much slower startup, an excruciatingly slow opening of Microsoft Word, and a slight distortion in the iCal icon in the dock. What is wrong, and what can I do to fix it? Also, is it possible to do a system restore on Apple?

I had a similar problem when I installed many fonts. Im a design student so having lots of fonts is necessary. I found linotypexplorer X (should be on mac update) which is basically like itunes for fonts. As i only use a few fonts i only keep the ones i need installed. Im able to view uninstalled fonts and all these fonts dont slow up my system.

Scott