Questions about Boot Camp

Hello everyone

I tried to run the Boot Camp Assistant, and got the following message:

"the Hard drive cannot be partitioned because some files cannot be moved"

Due to research it is my understanding that i should reinstall OS X

But i was wondering:

Can I partition my drive via disk utility and install windows that way?
Is there a way to move these unmovable files?
If I don't know where my original install disk is, what are my options?

thanks!