Your USB port(s) will will either be 1.1 or 2.0
Some PC's, just for added confusion, have the front USB ports as 2.0 enable but the back ones as 1.1 (or it could be vice versa - I can't remember - the point is, they're different).
The difference is the transfer rate.
USB1.1 - 12mbps
USB2.0 - 480mbps
You can tell if your USB ports are 1.1 or 2.0 by going into the hardware properties of your PC. If it your USB ports/hub shows up as "enhanced" then they are USB2.0, otherwise they're USB1.1
The iPod mini will work with USB1.1 but it'll be slow. You can add a USB2.0 card for £10-15 and it's a simple install if you can hold a screwdriver and you are running XP.