Mac or Windows?

Hi,

I am willing to buy a personal computer with good capacities for flash, photoshop, after effects and 3d Studio Max. However, I don’t want it to be more expensive than $1000 because it just can’t happen :P. Alsoooo, I would like you to advice me on whether I buy a Mac or a Windows because I know most graphic designers use Macs… but what about compatibility. I would also like to know what should be the characteristics for the system (RAM, HD, ETC) to use the mentioned programs with no problems.

I currently have a Windows XP with 128RAM and that is just slooooowww. It’s like 3 minutes to enter Photoshop and 3 more to make a new document :D.

I would really appreciate any advice, and if you point me out with examples on the internet it would be awesome.

Thanks in advance!