You were all correct.
The Install from an External DVD did seem to "hang" a few times, but after maybe two hours total for the Install, my Mini is running Vista Ultimate and it truly runs well! I'm actually quite surprised at how quickly Vista runs on the 'mini'... it actually runs Vista Ultimate better than I've seen on any other PC I've owned.
I installed Vista Ultimate (stripped via vLite), then installed the Synaptics driver from Synaptics site, and then I ghosted the drive, to ensure it wont take that long for the 'shell' to reinstall in the future, should I need to.