The best setting you could have possibly done for your box is something you already did: set the output resolution to it's highest setting - that is 1080i.
I have a Comcast DCT 6200 cable box and presently have the ?User Settings? set as follows:
TV Type 16:9
YPbPr or HDMI OUTPUT 1080i
4:3 override off
This to me is using the CC box to upscale all inputs, even the 480 to 1080i. This seems to do a decent job even with SD content. What I?m asking is what would be the best setting on the cable box to take full advantage of the 52a850?s upscaling and overall functionality? Thanks