What size and type of screws do you use on Melamine wood?

[wilomn]

i don't see how that would stop it from tilting.

i'm thinking of getting that ultra thin wood (not too sure whats its called) that is used behind dressers as the back then nail it in??

If you secure a brace to each side and in the middle, it will keep the unitl from tilting sideways.

A back is even better. I think the wood you're thinking of is Luan, it's cheap.

You may want to give some thought to pegboard too.