No, 2 hours is not normal.
If it can handle Vista, it should be compatible with no problems. I have run Win7 (RC) successfully on 4 older motherboards that are from 2004-2005. And there weren't any specific Win7 downloads available for them.
What motherboard is it? Make & model will be helpful. If this has downloadable drivers for Win7, then the rest of your system shouldn't be a problem.
You can check for other hardware & software compatibility at MS click here, & on one or two forum threads like click here. G