Does Zoomed 4:3 content look abnormal?

Yes, some plasmas zoom and stretch with better results than others.

Yeah, it does look weird using the 16:9 setting on 4:3 content, giving me a headache even when I watch just 5 minutes of it.

I use the Zoom1 function, which fits the 4:3 width to the sides of the screen and keeps the proportions correct, while chopping off some of the top and bottom.

Are you using the stretching mode especially for converting 4:3 to 16:9. The one that strecthes the outer portion of the picture more and might slightly crop the image too. Its usually called just, panaroma, side strecth etc.

They usually look a little better then just stretching the sides of a 4:3 image to 16:9. However, its far from perfect and objects and people still look a little distorted. The mode on some tvs seems to work better then others. I noticed the just mode appears less out of proportoin on my panasonic plasma then using the panorama mode on my Samsung lcd.

4:3 zoomed, stretched - whatever looked weird on my Samsung DLP.

With my Pio 940 plasma it looks much better - but it's still slightly distorted - but not nearly as bad as it was in my Samsung.

I could never bring myself to look at stretched 4:3 stuff on the DLP but I find myself not minding it nearly as much now with the Pio.

Here are a few good threads, with pictures, discussing the stretch modes on two of the leading brands of Plasma:

Panasonic Consumer and Industrial Model Stretch Modes

Pioneer Consumer Model Stretch Modes