I've just bought a used Nokia 5140 (the rubbery one!) and I've got rid
of the wallpaper so that when it's in standby there's just black text
on a white background, but when I go into the menus there's still an
annoying pattern of curved lines on the screen in the background.

I can change the colour of the pattern but I can't get rid of it. I've
reset the phone to factory settings and it's there still.

I am I missing something here or do I just have to live with this!?