Yah, all of those bikes look like junk. The "Sherpa" is the only one worth perhaps a drive to see if it fits.

If you're just going to be tooling around town, avoid all those aggressive-looking full-suspension bikes.

That's good advice above to look for a local shop that sells used bikes; they likely wouldn't buy any of these because they couldn't resell it.

Look for any rigid (or at most front-suspension) mountain bike from a reputable brand like Trek, Specialized, GT, Giant, Gary Fisher, Marin, etc. If a bike shop is selling a used bike like that, they will have tuned it up and it will be very reliable. If you find something like that on craigslist or such, chances are a cheap tuneup can get the bike to be in very good shape.