Base 2 + Tai verbs
 

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????

Corrections below (In bold).

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)>>>polite speech
is this right?

And another question.. how do i get the negative form? I've read somewhere that I say:
ikitakunai >>>>this is the correct negative form
but somewhere else I've read that I have to say:
ikitaku wa nai >>>>NOT a ~tai negative form
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)>>>>NOT a ~tai negative form
3)ikitakatta (negative plain form) >>>>past tense plain
4) positive plain form????

See below:
(plain) ikitai/ikitakunai
(polite) ikitai desu/ikitakunai desu

(negative plain) ikitakatta/ikitakunakatta
(negative polite) ikitakatta desu/ikitakunakatta desu

So how do you translate "I didn't want to go" in the plain form?

I don't want to go. (Ikitakunai)

I didn't want to go. (Ikitakunakatta)

and how do you say "I didn't want to go" in gentle form?

Is たい a special class of I adjectives? I learnt that to make negative of I adjectives either form くないーくはない　and くありませんーくはりません　are correct.

Yes, the form used with ikitaku wa nai is not incorrect.
It just carries quite a different nuance from simply saying ikitakunai. In other words, you can`t always substitute one for the other.

Yes, in a way. It is conjugated exactly like an い-adjective.

The red highlights are not correct.

行きたくはない and 行きたくはありません are things that can and are said. I`ve never heard anyone say 行きたくありません, though it is technically correct.

今日の運動会行きたくはないんですけど、行くしかない ･･･　親ってつらいものですよぉ

それは親の義務なんです、行きたくなくても。
/says someone without both children and an undokai to go to. have fun by the way.