Rbinck, Thanks. Sounds like fixing that will be a start.
PaulC, No, the bars are about 2-2.5 inches on both top and bottom.
The native resolution of my Dell is 1366x768 WXGA.
Jerry, Thanks for the directions. I also have a Motorola HD-DVR from Comcast. I'm not used to handling it other than changing channels and setting recordings, but hopefully I'll get there to set 16:9, although I wouldn't give odds

Shouldn't the tech have done this?
While I have you all here, let me ask another question. I recently attempted to view local stations OTA with a Phillips antenna that I had used in the past. My current TV is a replacement of an identical Dell, but I had good reception OTA with the old set (audio problems led to the exchange). I wanted to see if my current HD clarity problems would still exist independent of the Comcast box. So, I hooked up the antenna, switched to Digital TV port, and found I could no longer use the remote to get to digital stations. If I pushed 2, I'd get to CBS, but there was no way to get to 2-1. Pushing the "Channel up" thing that I used to use did nothing. Same for all other local stations. So, somehow I have lost functionality of OTA reception of HD on this replacement set. Do you think it's a problem of the TV, or has Comcast done something to turn off this avenue while the DVR is installed? Although I have cable now, I want to retain the ability to go OTA in case I end up moving the TV to a bedroom, or some such thing.
Thanks for your thoughts on this.
Jeff