Also, a DVD cannot hold enough data for an HD Movie. You must recompress it (a lot) to make it fit on a DVD...especially a single layer DVD which 99% of the recordable media is. Dual layer media is just as expensive as buying a movie dvd, so it defeats your purpose.
You'll have to wait until next year for something like this when the HD DVD format is available. But, don't expect the recorders to be affordable for a while...maybe 2007.