i have this mobo. what you should do is just install nforce software, it loads all drivers almost automatically. than you need to update the driver for one of the built-in network cards. are you trying to manually install the sound driver by pointing it to a config file?
if it cannot find a file you should look at the filename it is missing and browse the cd for the folder which contains this same filename, its on there. some drivers are buggy like this sometimes. dont know if you can delete the driver and reinstall it, if it was me i would reinstall operating system since you have not done anything yet. that probably is too cautious, but why not? installing software is fun