I have a few dark spots on my skin and I was wondering if mircodermabrasion would work?

Probably. Microdermabrasion will often lighten up dark spots, depending on where they are on your skin, and what caused them. But i would strongly suggest that you find a dermatologist with an mda machine, and not go to some spa, where the person doing the mda has no idea what caused your dark spots, and may be treating you when you should not be treated.