I didn't notice any stretching, and I'm using NS6.2.1, windowed (meaning not full screen), on a 1024x768 resolution-using 17-inch CRT-monitor. Is that enough information?
As for code-compliant sites though, I recently tried posting something on the Syberia2-forums.

NS6.2.1, couldn't type, NS 4.76, couldn't type and it said there was a script problem. Opera 6.04 (yes, I still haven't upgrade yet), also no go (still script problem), and while I could type something when using IE4.01 SP2 (although there was still a script problem), I couldn't post the text I wrote! (Talk about standards-compliant). What
did work though, was (yes, I'm sure you know the answer by now) Internet Explorer 6 (which I tried on my laptop at work)! So I'm pretty sure that's not a YaBB or eZ-board.

Goodbye Syberia2-forum!

I'll stick to this forum instead.