@paok1970,
paok1970 wrote:Do you find the sentence below correct?
What's this have to do with Christine?
If so, what does 's stand for or is short for?
I do not find the sentence correct. It includes, however, a form sometimes found in casual, non-standard, spoken conversation. The following are correct and possible:
1. What
is this to do with Christine? 'What is' can be shortened to 'what's'.
2. What
does this have to do with Christine?
The sentence you gave is a confusion of the two forms.