Advice on upgrading for MTW2

Planning to buy MTW2 in one or two weeks but i am not sure how well my current computer will fare so i am planning to upgade it and was hoping you guys can give me some advice.

Current specs:

Intel Pentium 4 2.8E GHZ
Corsair 512MB DDR 400 CL 3
Eagle FX 5500 256MB

My motherboard is able to suppport up to 4GB of RAM and i am planning to either upgrade my RAM to 1GB or 2GB and what graphic cards do you guys recommand?

How well do you guys think my current specs performance with MTW2?