Shimano hydros are better than Tektros,but what's really important is how the bike fits you and how you like the ride/handling. Can you test ride or at least sit on any of these bikes? That's the best way to choose.

If you absolutely can't,then at least look up the frame geometry of your old bike and compare it to the ones your looking at. That will at least give you some idea of how it will fit. But unless you're an experienced cyclist who's owned many bikes of different styles and knows exactly how they fit you,it's best to buy a bike you can test in person. Are there any co-ops/bike kitchens in your area? They would be the best place to start for a bike on a budget.