<< Which one is better the 4.38 or winXP drivers? >>
I`m using the latest version(4.38a) in my WinXP and they are just newer version of the default ones included in WinXP,the new AGP driver (in the 4.38a) is supposed to give you a very slight speed increase.
As for stability well no problems here,I believe the default drivers that come with XP are 4.32 or 4.33(not sure on this).
The latest 4.38a VIA 4 in 1 drivers are for all Microsoft Operating systems including XP,up to you if you want to install them.