Fast-growing ground cover?
Hairy Winter Vetch
http://en.wikipedia.org/wiki/Vicia_villosa for green, or phlox
http://en.wikipedia.org/wiki/Phlox for color.
Vetch also fixes nitrogen, and is a good companion to stuff like tomatoes. You can maintain vetch as a short ground cover with good mowing discipline, but if you let it get legs it will get thick stems which are not conducive to being a lawn substitute.
If you are looking for a lawn that, after getting it in, is both low maintenance and looks good, try zoisa
http://www1.zoysiafarms.com/?gclid=CIqCqNzZwKgCFUff4AodPQinqQ . House down the street has a zoisa lawn that browns around Thanksgiving and greens back up around S. Paddy's Day if it warms enough. The husband died about 3 years ago - he was outside every day puttering and doing stuff and maintained his yard with a passion. She is not so interested but keeps the lawn and the flower beds around the house quite well - she's let the zoisa fill in the flower beds he had scattered about the lawn - took only 2 years or so. Talk about a weed-free lawn! And it gets mowed only 2 or 3 times a season and survives on natural rainfall. I looked at the stuff once but moved before I got the urge to try to cut holes for plugs in Virginia Piedmont red clay (reinforced concrete when dry, sucking ooze when too wet), needed about 3 tons of sand and 2 tins of lime tilled in per the Extension Agent if I wanted to grow regular fescue which is why I looked at zoisa.
For windbreaks, avoid poplars unless you like picking them up. Willows are water-suckers and spread too much for my tastes. OTOH, willow birch is nice. If you like show, look at tulip trees
http://en.wikipedia.org/wiki/Liriodendron .
stay safe.
