Personnally i wouldnt recommend to go vista atm. Experienced from the beta version, it is a very demanding OS which require 1G RAM minium and good graphic card. With microsoft os history, i will said wait after 3~6month release then you get it. Unless is preload with your pc. But no harm to get a pc spec that can run with vista in the future
For the question, personnally i will depends on how much processor power you want from your spec. Surely, $1.5k can get a very decent pc spec that outrun mac with the same price, only if you DIY it.
A G4 spec will be slower than current pc spec. But load it with OSX, you gonna have a very stable OS and good production programs. (It will crash once in a while depends on how you use it though) and somehow the it last longer. My G3imacDV is still working and loaded with OSX10.4
If you not gonna use it for gaming, maybe i will recommend save out a bit and get the intel iMac with a big HDD.
For the question, personnally i will depends on how much processor power you want from your spec. Surely, $1.5k can get a very decent pc spec that outrun mac with the same price, only if you DIY it.
A G4 spec will be slower than current pc spec. But load it with OSX, you gonna have a very stable OS and good production programs. (It will crash once in a while depends on how you use it though) and somehow the it last longer. My G3imacDV is still working and loaded with OSX10.4
If you not gonna use it for gaming, maybe i will recommend save out a bit and get the intel iMac with a big HDD.