Yes Handbrake is great and you can't beat the price - it's free. But note that the latest release is only compatible with Mac OS X Leopard.
"HandBrake 0.9.2 incorporates many major and exciting changesincluding full support for the AppleTV Take 2 and the latest iPhone/iPod Touch firmware."
I love isquint...if you have any old home movies in an mpeg format that you want converted to mpeg 4 it works great for that also! Plus once you've converted it you can upload your videos in iTunes and play them on your iPhone or iTouch in my case..