Oh, I see your point now about wanting to put on OS X. My comment was just about a good computer, based on your suggestions of wanting a Dell or similar. Yeah, I’m agreeing with cwilbur. This isn’t the route to go if you really want OS X.
If you have already learned the Macintosh tools for your eventual use of the computer, then you should pay for it and get support when needed. If you can learn the tools on XP, then buy one of Eambos’ computers and run XP or Vista.
By the way, if this is related to your question about opening an animation business, I hope you are aware about laws or regulations against using pirated software, or penalties that may arise from doing so (seeing as it is not permitted to run OS X on non-Apple hardware). It’s very improbable that you’d be found or punished, but the odds are not zero. Also consider, you will be able to count the computer and possibly software as a business tax deduction if you do decide to make a business, thus offsetting some of the cost against buying any computer.