You should play the first. It's better than the second in my opinion.
As long as I can have Garrus in my party again I'll be set. I almost jizzed fucking everywhere when I first met him again in ME2.
Garrus is the best character in the series imo.
I suddenly realized something that we're am certain to face in this game, choosing between Cerberus and The Alliance. God dammit I hate this wait!