Greg (if that's your name

), I'll tell you about the setups I use for my 1292.
I found info elsewhere stating that the sweetspot for the 1292 in 16:9 setup is indeed 1440x960 as suggested by Tim. I use this, and have 4:3 setups also, with a resolution of 1440x1152. Originally, I set up the resolutions with refresh rates of 72 and 75 Hz respectively, for NTSC and PAL (thus having 4 different setups all in all).
The 16:9 setups are done by 'squeezing' the image vertically with the RGB size control on the projector. For this and the 4:3 setups, I use the 4:3 and 16:9 circles in the THX optimizer included on many DVDs. Beware though - just yesterday, I discovered that on the U.K. reg. 2 version of Star Wars:ATOC, the 16:9 circle is wrongly flagged as 4:3...

Caused me some consternation when setting up a new resolution/refresh for NTSC video material. Maybe others could have this error also, so make sure you are indeed seeing 4:3 and 16:9 respectively. I've used the optimizer on Treasure Planet, U.K. reg. 2 before - that one is ok.
After using the above settings for more than 6 months, I decided to try refresh rates of 48 and 50 Hz instead of 72 and 75 Hz. Had read a lot of positive things about this, but was reluctant to try it, as I'm very sensitive to flicker on CRT computer screens (can't stand looking at a CRT monitor at 60 Hz). The flicker is evident on the projector when looking at the desktop with brighter colors, but much to my surprise, I don't notice it at all when viewing DVDs from my normal seating position.
It gave a marked improvement in sharpness (very evident if you go back to 72/75 after using 48/50 for a while). The biggest advantage for me though is that it has virtually eliminated my warmup-time. With the higher refresh rates, it would take upwards of 2 hours before the convergence stabilized. With the lower ones, it's very good after a mere half hour.
If you use this bandwidth calculator:
http://www.myhometheater.homestead.com/bandwidthcalculator.html
You will se that the above resolutions with 72/75 Hz refresh gives RGB bandwidths in the 150-190 MHz region, whereas 48/50 falls around 100-125 MHz, which is better suited to the 1292's 120 MHz bandwidth (Some sources says 135 MHz).
Hope this helps a little. If you like, I could email you an Excel spreadsheet with my exact Powerstrip settings (front porch, back porch etc.). Don't know if it would work for you at all, as these setups are a combination of what the PC throws at the projector and what the projector recognizes, based on what it's been fed before. Do remember to hit 'memory' for each setup on the 1292...
Cheers,
Erling