DDHH, let's skip all the other suggestions about software on the PC for the moment, and see if you can help us with the "Is the disk finalized or not?" issue.
Take one of those DVDs that plays in your Toshiba DVR670KU, and load that into your computer. I bet it doesn't play, does it?
Next, with that DVD disk still your computer (probably in D: Drive?), go to your MY COMPUTER icon and double-click to open it, and then browse over to D: Drive and see if any file-names are displayed. Any at all. I have a feeling "no", and you may even get odd errors like, "No disc" or "No valid disc".
If this occurs, then we've got a "No Finalized Disk" issue.
A "Finalized Disk" has a tiny command embedded in a DVD Blank saying, "OK, that's all, folks!" and any other DVD player will look for an Opening Byte and that closing Finalized Byte first, then the Player will start reading from the beginning's data (the movie files).
When DVD players don't see that Finalized "That's all, folks!" command, they don't even bother trying anything else. They just sit there - "Whatcha want me to do with this? Spin endlessly?" Yes, that's what they're thinking.
So, you have to re-explore your Toshiba DVR670KU and figure out what buttons you need to push to issue the Finalize Disk command. It might be in the SETUP menus - probably a checkbox like, "Finalize Disk?"
EDIT: In my next REPLY, note that Toshiba uses the phrase "MAKE COMPATIBLE". Du-uh.