Obviously the dated wallpaper and green Corian counters are not helping...

Stay with white so it blends in.

I agree about the wallpaper.. The counters you may be able to live with- I think even if got nice new appliances, you'd notice the wallpaper even more as being dated.

I would take that down, and would either go with another white fridge, or stainless. I feel like the back stainless isn't back enough to go with the other appliances, and it might break up the kitchen too much, visually. (Does that makes sense?)

I agree - stay with white for now. It will blend in and probably be less expensive. And when you are ready to update the entire space and replace all of the appliances you can change to stainless etc.

I think the black stainless or one of those slate colors would look good, and "go" better with the wall ovens, etc. Stainless would look okay too.

I would go plain stainless (better for future matching and I have heard the black stainless scratches) or plain white.

I would get a white counter depth refrigerator. Agree the paper should go while you're at it.