[lucagalbu]

Hi there!
I have a problem with base 2 + tai verbs.
If I have to say I want to go I say:
1) ikitai (plain form)
2) ikitai desu (honorific form)
is this right?

And another question.. how do i get the negative form? I've read somewhere that I say:
ikitakunai
but somewhere else I've read that I have to say:
ikitaku wa nai
What form is the right one?

And about the past form, is this right?
1)ikitai deshita (positive gentle form)
2)ikitaku wa arimasen (negative gentle form)
3)ikitakatta (negative plain form)
4) positive plain form????