I would say that you are over paying for just the computer. You can get a brand new mac pro (2GHZ & 2GB Ram & a 20 ” display for only $200 more.
If that system was posted on creagslist or any other online listing I would report them for trying to sell Illegal software.
Where you are just starting out and you feel like you must purchase look into a iMac. I usually recommend not purchasing until you know what you need. Take a class first, decide what format of video you want to work with (different types of video formats will have different computer hardware requirements)
Basically educate yourself about what you need before you drop that much money on something.