we vacuum sealed most stuff (and then I fell pregnant the next month!) but Im culling most things between 2 and 3, mainly because 1)a lot was hand me downs 2)DD was a reflux baby, so the stuff is already heavily used and 3)we might be stopping at 2 kids.
I had clothes vacuum sealed in a sealed box (which was then wrapped in plastic) in storage for 5 years and they came out fine (just musty)