18 Wheels of Steel Convoy running dual display at 3360x1050 and the proportions are way out, all circles are oval. I seems as if I would have to choose 3360x2100 if it was even an option. Any ideas on how to fix this issue?

I'm running:
XP Pro

AMD Athlone 64 X2
Dual Core 6000 3.02Ghz

3.25Gb Corsair XMS Ram
PC2-5300 (667Mhz)

EVGA GeForce 8800 GTS 320Mb

Any information would be greatly appreciated.