Help! Picture settings on Pioneer DVD recorder

[brownrog]

Is there anyone technical with a Pioneer DVR-420, 520 or 720 who can help me with this question please?

What are the best picture settings to use for RGB input from a set-top box and RGB output to a projector? My set-top box is a Thomson DTI1000 DTTV tuner and my projector is a Panasonic PT-AE700 (LCD). The recorder is a DVR-420HS (80GB HDD + DVDR). It offers input picture setting presets (setting picture quality for TV and external inputs) of:

Tuner / VCR / LDP (Laser Disc Player) and 3 user configurable presets.

The manual says the Tuner preset is suitable for general TV broadcasts but I'm not sure if this would apply with RGB external signals through the SCART (from the STB) or just to signals from the integrated analog TV tuner (which I never use). I don't understand how you choose what to set on the manual settings. The picture looks best to me on most material using LDP of all things but if anyone knew the theory of an answer I'd be interested to know.

The other picture setting is for picture quality for disc playback, where the presets are:

TV(CRT), PDP (Plasma), Professional (professional monitors), and again 3 user configurable presets that I don't understand parameters for.

Which is likely to be best for a projector?

Questions rather techie, but is there anyone technical who might have answers?