I get that message with some .avi's that maybe aren't pal, but an odd resolution and 23/24 fps..
I pick NTSC and usualy auto for the rest. Then at the end it says that.

Sometimes I say yes and the DVD's still play on my NTSC only dvd player/tv.

What does it actually do? Does it make a NTSC dvd which somehow has 25fps videos on it? and why?
Shouldn't it just down pulldown for 23/24fps vids?