I'd really look at the Schwinns being sold at Wal-Mart. After Pacific bought out the bankrupt Schwinn/GT (which makes me also want to avoid theGT I-Drive system....replacement parts may become hard to come by as Pacific shifts away from GT production), they began marketing Schwinn in Wal-Mart, as Pacific had stated it would seek out mass marketers.
Unfortunately for Pacific, Schwinn already had tons of frames, components, etc. coming for the 2003 season. From what I've seen in Wal-Mart, the Schwinn frames are exactly what we sold in our shop before Schwinn went bankrupt. The components are the same, everything is the same except for the rear wheel being bolt-on instead of a quick release.
If ou want a decent bike, then go to your local bike shop and get fitted to a frame size. Unfortunately, these bikes in Wal-Mart, on Sports Authority, et al, assume everyone will fit on a 17/18" frame, the "standard" one-size-fits-all frame size. But much like shoes, a 17" frame does not fit everyone just like a size nine shoe doesn't fit everyone.
But heck, don't take my word for it, even though I own part of a shop........go to your local shop, get fitted, check out their used section for a decent deal.