を or が?

[GenjiMain]

Hi friends. If I wanted to say "What do you not want to do?" would I say 何をしたくないですか or 何がしたくないですか.

Also, out of interest, would you say in daily casual conversation between friends this particle would be dropped?

Thanks in advance :

 

[Toritoribe]

If I wanted to say "What do you not want to do?" would I say 何をしたくないですか or 何がしたくないですか.

Both are correct.

Also, out of interest, would you say in daily casual conversation between friends this particle would be dropped?

Yes, but it's more commonly omitted in affirmative questions, e.g., 何したい？.