Thanks to all who have posted already. The information has been invaluable.

I've got an HL-P5063W set and have been frustrated trying to get all of the discrete codes to work. I got the same info from Samsung that many in this forum already have -- and had essentially the same experience (i.e. that a bunch of it is just wrong!).

I finally decided to do the brute force method: I used bmontini's Excel spreadsheet to create Pronto hex for all 256 codes and test them out to see what the 'actual' codes were. I was able to find discrete codes for all the inputs, but couldn't get any of the aspect ratio codes to work.

The (hex) input codes that work for me are (* = different from Samsung's tables):

Power On: 99
Power Off: 98
Antenna: 1B
AV1: 84
AV2: EB*
AV3: EC*
SVideo 1: 85
SVideo 2: ED*
SVideo 3: FB
Component 1: 86
Component 2: 88
PC: 69
DVI: 8A
HDMI: 8B

I've had the same issue with the 'Power On' that many have (i.e. it only works for a few minutes after power down).

Has anyone had any success getting the aspect ratio codes (i.e. 'Zoom1', '4:3', etc.) to work? If so, what codes have you used?