Welcome To Bike Forums, PapaGanoosh!
This is really not the way to search for a bike. First of all, you should already know your approximate frame size. I mean, if you're 5'8" and the bicycle is either a 58cm or a 60cm frame size, then you're just spinning your wheels, for nothing. Neither would ever fit you....
The next most important thing when buying used, is to either be knowledgeable about bicycles yourself, or to know someone who does possess such information about bicycles. They would need to accompany you when assessing the overall condition of the bike.
Thus far, I can tell you that the bicycles posted appear to have chromoly steel frames, and that's a very good prerequisite for purchasing a used bicycle. Now since, both bikes that you've posted apparently need some level of reconditioning, I would suggest that you find out their sizes, before any further consideration. If they turn out to be more or less the appropriate size, then the next thing to consider would be their condition and riding comfort level. Since neither is in good riding condition, either purchase would be more like a crap shoot at this point. That's to say, that there is some amount of risk involved in making either purchase. However, it is better than buying online, and that's for certain.
Your expert who assists you in assessing the overall condition of your bike, should be looking for the degree of rust accumulation, any weld issues, and any signs of structural damage. He should also be able to detect any mechanical malfunctions.
Finally, he should be able to tell if you look as though the bike fits you. After the expert's intial inspection of the bike, he will do a repeat final inspection after you've taken it on a twenty minute test ride.
If you suspect in the least that the bike is too large, then don't buy it!
Try to locate a bicycle co-op in your area, so that you will be able to repair, upgrade, or otherwise recondition your bike under the watchful eyes of seasoned bicycle mechanics.
If you don't need tires or wheels, $100 should cover the average tune up with change to spare. Of course, you should always buy a new saddle and new grips, just to make your bike feel 'new'. Therefore, take an extra $100.