No, they aren't the same. A hostal is a small hotel, usually located on one or two floors of an older apartment building. They tend to cost less and don't have the extra services you would find in a regular hotel. Even in buildings that have elevators, you might encounter a few steps or other mobility limitations in a hostal, since they are generally located in regular buildings.

A youth hostel (the English word "hostel" spelled with an "e") is an albergue juvenil, which is another type of lodging.

There are plenty of hotels in the center of the city that are wheelchair accessible.