i say get what you want. if an old vespa gets you excited to two-wheel, then get one.
i've never owned one, but if i were to get one, i'd go for a late-70's to mid-'80's P200 or PX200. these can be sweet bikes, and respond to mild bolt-on mods quite well--as well as total hot-rodding.
the thing about them is--as one poster implied--they can be as cantankerous as our beloved mopeds. but like our mopeds, they can be reliable to a point, as well. it's all how you approach it, and how you build/take care of it.
as far as the poster who implied that scooters are ugly, i myself find vespas to be incredibly sexy bikes. never my thing, as i'm a moped-MC guy, but i see the beauty in them, for sure. (edited)