graphics card setting

hi,

my brother has Asus A6J, with Mobility Radeon X1400. He has recently reformated his computer and did clean instal of XP. Before he formated, he was able to play Tom Clancys Rainbow 6 vegas 2, not on ful detail, but he was able to play it fine-its a FPS so you need a decent amount of frames per second to be able to play well.
after clean instal, we installed all the utilities and drivers form the CDs that came with the laptop, did all MS updates, found lates graphics drivers, but for some reason, the game is not playable even on the lowes details. (He has 2,5GB Ram).

1.) What is there to do to enhance the function of GPU?

2.)Im not still sure if he was playing on his native resolution. when we lower it, the game performace obviously increases. the thing is that its not full screen, but on 1280x800 screen, it stays small. so there is a chace, that before, he was using lower resolution, but for some reason the game was full screen. is there a way to do that?

thanks for any tips on how to deal with the problem

 

Alt-Enter should toggle between full-screen and windowed modes.