If you can't find the extra bucks go with 5200, easy choice. Don't go with the MX4000 they aren't going to help you out with any games now....
The FX 5200 is DX9 and has large enough memory amounts to help a bit.
There are only Two things in life i regret doing... 1. Selling my Soul for Cash.... 2. Buying a Compaq.... I should have kept the Cash, huh.