To mac or not

so i was watching the 2004 WWDC Keynote, and I started thinking about getting a power mac g5. the dual g5.

i had some questions for you mac geeks.

.how much ram does a mac use? on my pc 256mb of ram craps out after 30 minutes when i’m doing serious video.

.do you necessarily have to buy an airport to connect your mac & pc, or can you just do a linksys router?

.does mac support combustion and after effects? i’ve really been wanting to do some of that stuff…

.how long do macs generally last, both speed wise and hardware-wise (like, will it still be fast after 4 years, and will it fall apart after 4 years)

.i was reading on the apple website about how the dual g5’s have half the FSB of the processor speed. would or would not this cause a bottleneck?

.is mozilla/firebird available for mac?

.is a mac really worth the $1999?

This is a really big decision, and I just don’t really know what I’m getting in to. I blogged about it (for more info on what i’m thinking).

Thanks for any helpful tips/advice/feedback on this.