yea; \winnt\ usb.inf is definately a windows/ms driver; thats not the one you want installed there.
My advice is to go through the installation process, do whatever m-audio want you to do; which will set up the programs (mixer exe etc) and then plug in your card; windows should pop that dialogue up.
have a look on the CD for the actual .inf file (i.e. the driver) It may be in a folder neatly labled driver\2000\ like it was for my audiophile, or it might be inside a .cab file (compressed archive for setup.exe's to use.)
if thats the case, you can either use winrar to open it (it'll be called data.cab or simmelar) extract to a folder and dig the inf driver out of there, OR run the setup program until the very end stage, get it to install everything but make sure it doesnt exit, and then have a look through your temp files for any .inf's while setup is still running. either way what you're trying to acheive here is to get your m-audio driver in instead of the one that it wants to install. go for the "install from a specific location" rather than the auto-scan for driver. If you find the .inf file but can't get it to install from specific location, then find it in an explorer window, right click and hit 'install' - and if that doesnt work, the only other thing I can suggest Is that you try get the latest version of your motherboard's USB hub drivers from the net.
A friend of mine had issues with USB and his mobile soundcard (it was m-audio aswell) and we've come to the conclusion that it is because his motherboard is too old; it was working fine until he had to downgrade to an old mobo. so, If yours is an old motherboard you might want to grab some tissues because we've been trying to fix his for weeks. no chance of it happening; usb is something that was brought out before it was entirely perfect and he's going to have to get another motherboard...