So I guess all those four-digit price tags on HDTV sets are just typos? 
That is most certainly not true. Even 35mm films from the thirties contain much more detail than is ever transferred to a DVD, and by the sixties 70mm films with twice as much area and even better definition due to advances in chemistry were common.
Upscaling a DVD will get you a smoother picture, but it can’t replace the detail that was discarded when the negative or print was scanned for DVD transfer – and that’s a lot of detail. You can scan carefully-shot 35mm film at about 5300 x 4000 and still be pulling out useful information. (Of course, when you’re dollying the camera around and stuff, you’re going to lose some detail.) It’s common for people who are working with digital film restoration of films from the '30s and '40s to scan at 4000 x 3000 if the aim is to print back to film, because there’s enough detail even in those old films that you can’t scan at a lower resolution without discarding too much information.
HDTV doesn’t come anywhere near chemical film when it comes to recording image detail. As long as the transfer is made from film that hasn’t degraded too much (or has been carefully restored) any film that’s transfered to an HD DVD format is going to look just as sweet on an HDTV as the latest episode of The Sopranos.
Hell, if twenty years from now video technology progresses to the point where the average consumer can afford a floor-to-ceiling wall-sized LCD display, people will still be able to go back to antiquated film prints and rescan them at 4000 X 3000 for a huge increase in image quality for the new SHDTV standard. 
Please don’t make me explain the difference between “cost” and “price”.