The Bicycle Repair Shop does rentals by the hour or by the day. They have reasonable rates. They have solid, lightweight hybrid bikes so you can tackle train tracks and brick streets and hills. They also have road bikes for the more experienced. You can reserve online in advance. You get a helmet and a lock with your rental. The staff in the shop are friendly and will suggest routes and point out hills if you're new to the area. And believe me these hills are no joke!
Brakes come in a variety of designs depending on the age and style of your bike. Rim brakes offer more modulation but have less stopping power, so are more suited to riding on the roads. Disc brakes can provide huge amounts of stopping power so are best suited to off road riding, although ‘V’ rim brakes are also well suited to mountain biking. All brakes use a friction system to stop the movement of the wheel, so regular checks of the contact pads should form part of your regular cycle maintenance.