try getting version 1.4 of the game lmao...it might fix all your problems
(it might not work with your copy though for "certain" reasons, just try i guess)
In Windows you should be able to go into Display Properties and find Performance tabs and such for your card. Tuning it to lower/higher settings might render better gameplay. Mins sure does, i turn on AA&AF and the game looks MUCH better.
EDIT: actually this is NFSU2
isn't it? NFSU has the 1.4 out, i'm not sure about NFSU2. Go to the website and look for the latest patch.