Using FZ31S with Pioneer Plasma TV

Hello Folks

I'm really confused regarding the correct resolution setting for my Pioneer PDP-428XD plasma tv. I connect my Sony VGN-FZ31S to my plasma (via HDMI) to view HD movies and DIVX movies which are stored on the laptop's hard drive. The laptop has a native resolution of 1280 x 800 with NVIDIA GeForce 8600M GS Graphics 256mb dedicated. Up until today i was just using the setting "CLONE DISPLAY" in the NVIDIA Control Panel and whatever was displayed on laptop screen was duplicated on plasma screen. However watching movies with this setting gave me a couple of problems:
1) Video playback wasn't smooth, it was jerky in places on plasma screen (but not on laptop screen)
2) I wasn't allowed to alter any in-depth picture settings on the plasma when pressing the HOME MENU on the remote. Instead of getting AV selection, Contrast, Brightness, Colour, Tint, Sharpness, Pro Adjust, Reset, i just got: AVSelection, Contrast, Brightness, Red, Green, Blue, Reset.

So after playing about with the NVIDIA Control panel, i am now presented with the following options:
1) I can manually select the plasma resolution on the slider bar. The setting of 1360 x 768 is the best setting but if i make any setting using the slider bar, then HOME MENU on the plasma does NOT give me in-depth settings as mentioned in 2) above.

2) Alternatively instead of using slider bar to set resolution i can also use one of the settings below under NVIDIA Control Panel > Change the Signal or HD Format:
1080p50 HDTV
1080p24 HDTV
720p50 HDTV
non HDTV Signal
1080p HDTV or
1080i HDTV or
720p HDTV
576p EDTV
480p EDTV

If i choose ANY of the predefined settings in 2) then pressing HOME MENU on plasma remote will give me in-depth settings but none of the settings above give me a resolution as good as the slider setting of 1360 x 768.

So which display resolution setting should i use for my plasma?

Thanks