Your inner-tubes are one of the most critical components on your bike. Bontrager's are premium quality, standard weight tubes that keep you rolling. Get one more than you think you'll need—you can always use a spare.
Schrader valves are identical to those found on car tires. These valves are generally used on hybrid and children's bikes. Presta valves, which are found on most road and off-road bikes, are longer and thinner and feature a threaded tip, which must be opened to inflate (turn counterclockwise).