I don't see enhanced under my devices, but I know I have USB 2.0. I'm looking at my USB Root Hub.
Anyway, your transfer speed, IMO, is way too slow. It may be the Nano itself, as it uses a flash drive instead of the hard disk on my bigger iPods. But it still appears too slow. Apple has 8gb Nanos. That would require an overnight sync if your transfer speeds are the norm.
I suggest you try to narrow down the problem. It does not hurt to try iTunes, just to benchmark it against MC. If the speeds are similar, all it tells you is the problem is not MC. My guess is that MC is just fine and the problem is somewhere else.
I've had slowdowns similar to yours in the past and the culprit was my virus checker. This was the primary reason I totally eliminated Norton products from my PC. So you may want to disable any virus checkers to see if that helps. You could also disable any spyware checking to see if that helps. If your not running any virus checkers or spyware checkers, that may also be your problem (your PC may be infected or filled with spyware).
If you have access to another PC, that's another way to benchmark if the problem is with your PC setup.
If I think of anything else, I'll let you know.
Maybe someone else with a Nano could report their transfer speeds.
Maybe glynor has some suggestions on how to trouble shoot the PC. I think he knows a lot (at least a lot more than me) about this subject.