If you can, save up an extra 200 and get an imac G5 with the education discount. The frontside bus is considderably faster and overall performance would be dramatically better:
17-inch widescreen LCD
1.6GHz PowerPC G5
512K L2 cache
533MHz frontside bus
256MB DDR400 SDRAM
NVIDIA GeForce FX 5200 Ultra
64MB DDR video memory
80GB Serial ATA hard drive
Slot-load Combo Drive
$1,199.00
If your budget can stretch to it, get a G5 Powermac. In the long run it would be a better investment as you can upgrade it.
1.8GHz PowerPC G5
600MHz frontside bus
512K L2 cache
256MB DDR400 SDRAM
Expandable to 4GB SDRAM
80GB Serial ATA
8x SuperDrive
Three PCI Slots
NVIDIA GeForce FX 5200 Ultra
64MB DDR video memory
56K internal modem
but...$1,349.00
If you're serious about getting into editing, hold off for a little while and save up the extra cash. If you're willing to invest $1000 you don't wan't to invest it on technology that's on it's way out. The G5 range is the best direction to head in if you're going to be doing a lot of editing now and in the future.