Without a lot of headaches you will not be able to run OSX on a PC. And from what I understand one needs to be pretty computer savvy before attempting.
Vista is okay. It's an improvement on XP, but I've been a Mac user for going on 8 years, and there's no way I'd ever go back. Just using my brother-in-law's computer with Vista on it makes me frustrated.
For being a film student needing to do a lot of editing, a Mac is definitely the way for you. Macs have been one of the best systems for any creative work (video, music, graphic art, print production etc.) for years and its because they are no nonsense. When you're up against a deadline you can't afford to have system failures and be down for any length of time not able to use your computer. My 7 year old PowerMac has never crashed on me once. It has never given me one single solitary problem. That's just how they are, they just work. And my 7 year old PowerMac runs all the latest versions of OSX, MS Office, Adobe Creative Suite, better and faster than it did the day I unboxed it because OSX is written to optimize your system resources, no matter how old your system is.
Also, in 7 years, I've never had a single virus, no malware... and have never had any extra software installed to protect me from it. They are more user friendly, more intuitive, and just more everything than a PC.
If you weren't needing to edit films, I'd probably tell you that a PC will suit your needs. But I think you'll really be more happy working on a Mac. They are more expensive than a PC, but they will last you a lot longer. Never has a PC lasted me 7 years..... I don't know that one ever lasted me 7 months.