TomTom GO 700
Having used a bunch of navigation systems, this ease of use is just so important. Not a bad price ($750) for a portable unit. It isn’t built into the car, but sometimes that can be an advantage in that you can get rid of it when it gets obsolete.
It comes with a 2.6GB hard drive so there are no DVDs and it has Bluetooth, so that you can answer from the screen (I don’t know why you’d want to do that) and use its onboard speaker/microphone system like a handsfree system. More significantly, you can call any number in the navigation system from your phone.
Also it has a li-ion battery in it, so it can run up to 4 hours without being plugged in at all. The main con people have found is that screen is reflective so can be hard ot read.