I have the same problem. 8600GTS, Core2Duo e6300, X-Fi Audio, and 169.21 version driver. The menu delay is about 30 seconds, after that inventory delays are about 30 seconds too... it's 'cause of driver, but I don't want to install older drivers for this crappy game. I tried everything, disabling\enabling anything that can be disabled\enabled and there were no succes with this problem. (( The same problems in Vista too. ((((( I'm very, very disappointed. Excuse my English.

P. S. Only hope for 1.4 patch, but I think it's never be done.