several interesting problems win xp home sp3

hello all i've been having problems running gta san andreas ...the game ran at different speeds frist at a normal pace then very quickily, traffic cars would spawn inside eachother everything moved 10 times to fast, then go back to normal...this was happening every few seconds in ...i also got blue screens from time to time...i'm told this is do to to the amd processer, that i need cpu drivers..but i've never downloaded any befor even so san andreas ran properly although i would get a blue screen then sometimes...but this last time when i was forced to reboot ..i was confronted with an error message that i've never seen befor that says unable to load user profile do to in insificant sucurity rights ...i can't remember the second thing i'll write it all down and post the error if it'll help .....this ones well over my head and i do have a comfortable understanding of computers and windows xp...someone please help

 

alright the full error message is entitled user environment error ...which continues on with saying cannot load local user profile because of insificant sucurity rights..or corrupt local profile ...has anyone gotten this message befor ?