As I am not a native speaker, I'll reply with an extract from "Practical English Usage" by Mike Swan:
The negative <for would rather> is would rather not.
I'd rather not go out tonight. (NOT I wouldn't rather...)
So, 2) is wrong.
We can use would rather to say that a person would prefer somebody to do something.
I'd rather you went home now.
So 4) is wrong too.