How to answer interview question?

I am currently going over possible interview questions and possible answers, so I am prepared for my interview tomorrow.

The one that is currently going through my mind at the moment is the question: When are you available to start?

I’m a bit worried because the first week in May, I have to attend dentist appointments. I don’t want to go off to a bad start, by having time off to go for arranged appointments. It’s not optional to rearrange them.

I do want to start work, and am actively seeking, but how could I answer that question without coming across as ‘I don’t want your job’ when that is not the case?