I'm not sure about using NTFS with with Mac, but most Hard Drives should work with a Mac. I know my hard drive (formatted in mac's EFS) works with Windows XP. If nothign else, find a friend with a mac (or go down to a store) and try plugging your drive in. If it doesn't work, find another drive to back up your data on. reformat your drive in EFS and then transfer your data back.
Dont let this keep you from switching to mac. While mac's are overpriced, they are much better. The OS is so much more awesome than XP, not to mention Final Cut being one of the best NLE editors. (the best in MHO, but thats just waht i learned on). I've never met a single person who has switched and not been happier with thier Mac.
-Alex.
feel free to e-mail me with more questions