Picture this.... I have anti virus/anti spy ware software running, and I have a web page loading, and I am searching for a song useing Winamp while a song is already playing on Winamp...all at the same time. Is this considered server like multi use or would this kind of load on the HD still be considered single user use? I am trying to figure out if I would benefit from Native Command Queing.

It's single user use. A multi user use, would be distributing virus definitions to 15 clients while caching a web page and sending it to 100 people and defragmenting at the same time.

Of course, I'm adding some exageration, but you get the point. Much more file accesses than what you're doing. You have 5 concurrent demands, tops.