partitioning...

I have an 80 GB hd right now and I am wondering if I partition it into 2 drives, one being only like 8-10 GB where I put my windows xp OS and games on. And then the other drive where I put misc. files such as movies, texts, and all that bad stuff . Will these make my system run smoother? And would I need an OS on the drive with 70GB if im just going to be running the files off the OS drive? both NTFS. any tips...