While this sounds easy enough there are big issues and not legal ones
only... where would you get such a chip? I'm sure they are not available
"off the shelf". You'd have to find someone who could do some major
programming and fit it to the hardware interface of your DVD player.

I'd be willing to bet it would be almost impossible, but good luck and let
us know if you can pull it off.

If you know what you are doing go for it. However, you can fry out your chip
set. It is a domino effect. How you are going to unsolder up two 244 pins on the
chip?. Most people will just piggy back a new chip on the old one. You use to be
able to do that with EPROMS, but EMPROMS are old school now.

you'd be as well off spending a little bit of cash on a small form factor pc
with tv out on the graphics card and then setting up something similar to
mythbuntu on it? that way you can play your dvd's on it, along with all your
digital media (avi's mp3's mp4's etc) and use it as a digital video
recorder? small form factor pc's wouldn't take up much more space than a
standard dvd player, and would be so much more versatile, and a lot less
hassle than the "solution" you propose!

Broomster has a point.

I met a guy who purchases the apple mini, installs ubuntu and then
mythtv and then resells them as upgraded dvrs. Pretty cool.

If you wanted something very small - the Cappuccino pcs are really
small. I personally like the Shuttles. I have had some trouble recently
with my own computer but I have built many many of these in the past
with zero problems. Install 2 1TB drives, 2 video cards, quad cpu, 4 to
8gb ram and you could put it under the cabinet and it would be a awesome
DVR machine.

Not sure about soldering and stuff, but perhaps you could flash the ROM to
do what you want it to?