Janine,
If you are comparing this to the old VCRs, they had a tuner (analogue) for the recording channel, whilst you could watch a different channel on the TV set.
If you are relying on just one (digital) tuner on the DVD, it can only do one thing at a time.
You would need another digital tuner, to be able to watch a different digital channel (such as a simple "set-top" box).
Hope that helps.
PtG
December 2008