Nvidia Geforce 8800GTS good enough

[supre250]

What do you think of this card which im purchasing today plus 2 GB XMS 800MHZ DDR2 Ram
Expensive i know close to the best video card suitable to run all these new games and future
But my point is am i able to play better resolution than before eg.649x480 or 800x600 the best i can get of it without crashing
Previous video card i have is 7900GS Nvidia Geforce which some games are not able to perform to spectation
What do you think before i purchase the card

At present i have a machine
4200+ AM2 Althon 64x2
2x 512 MB dual channel ram
1x 320 GB HDD SATA 2 and IDE-200GBHDD and a DVD-R ROM
7900GS Nvidia Card

This machine is not able to play games at higher resoulution it crashes for some reason and its making me feel sick
I have install the latest graphic drivers and new OS eg.XP so dont bother asking for that type of solution its already done to no avail
Now im now decided to upgrading but want some input thanks

New upgrade is as followed
4200+ AM2 Althon 64x2
2x 1GB dual channel ram (NEW) 1.
1x 320 GB HDD SATA 2
8800GTS Nvidia Card (NEW) 2.

Is this oK to play the lastest and future games in better resolution without any more upgrades
Expensive is the main problem