Ian, many thanks for the cash back link! That's paid for the memory and part of the PD air leather cover I got for the NB100. i owe you a virtual beer!
I suspect that you are right and it's iTunes that is causing the problem. However, that's where I get my movies from. I tried playing the movies/tv progs purchased from iTunes with the Windows Media Player but they don't work. Also, at the suggestion of someone on the Toshiba support forum, I tried downloading the VLC player but same thing.
Is there a way of converting iTunes formatted Movies/TV?
I can now play the iTunes programmes but to avoid the slightly annoying ripple that appears about 75% up the screen when there's a lot of movement, I have to reduce the screen size to about 2/3 of the screen so it's not much better than watching on my iPod Touch.
Would you mind sharing with me the relevant settings you have on your NB100 to see if by duplicating them can get any improvement?
Many thanks