I'm sorta new to snowboarding and have been renting snowboards everytime I've gone but may be buying soon. I've looked on many different kinds of boards and don't know what brand to choose.
Are there any notable differences between different brands of snowboards?
Yes and no. There is a difference and range between the length, size, weight, shape (or camber) and flex of different snowboards.... but most major brands offer the full range of options across their different models (with a few exceptions).
Although you won't have a good frame of reference when learning to snowboard.... by time you figure out how to stop, turn, and ride around without falling down every 30 feet, the board you are using will start to influence your progress.
Generally, somewhat shorter, light, flexible (softer) boards are more forgiving for the kind of riding a beginner does. The short length makes them easier to turn and the soft flex helps keep the entire edge in contact with the snow as you traverse down the hill at slow-to-moderate speeds. A board like this will feel more 'responsive'
Stiffer, heavier boards require more effort (or technique) to maneuver, especially at low speeds. The trade-off is that these kinds of boards are more sturdy and more stable for high speed riding, or riding through choppy snow. Objectively, one might say that a board like this is a poorer choice for a novice rider because they require more rider-input and more speed to exert an equal amount of control over the snowboard...... but like everything in snowboarding, it comes down to preference.
Its perfectly possible to learn on either kind of board.