MythTV Progressive vs Interlaced problem solved (at least for me)

I've been working on my MythTV quite a bit lately. With the new baby, my hobbies have taken a turn towards things I can work on in short hour long chunks :). I've been having this weird problem with changing channels. When the channel changes, the auto-detect feature for Progressive or Interlaced video would incorrectly choose Progressive. I am using the PVR-250 card. It has RCA, COAX, and S-Video inputs. For some dumb reason I was messing around with using the RCA input. It turns out that anytime the cable box menu would appear on screen during the channel change, that the auto-detect would detect progressive and not interlace. All I had to do was use the COAX connection and it stopped having that issue. Additionally I was having some really nasty crashes when using the program guide. I read a few notes on http://www.gossamer-threads.com/lists/mythtv/users/ that suggested that my resolution should be closer to the video source itself. I had been running at 1920x1080 on my Samsung 50". But I'm not really doing much with HD feeds anymore now that Comcast has encrypted everything except for over the air channels. So I dropped the resolution down to 1280x768. That not only made the program guide more reliable but it also made it far easier to deinterlace and display a much better quality picture. I think my AMD Athlon 1800 is just barely enough for the HD stream. Trying to deinterlace and scale video to 1920x1080 is just too much for my cheap old MythTV box to handle. Note to self: Just because you can have 1920x1080 doesn't mean you should. Oh and also, stop using the worst possible TV signal (RCA) for video!