Bart Allen is a DC Comics hero. Also known as Impulse, he's a speedster from the future who travels back in time to cure his growing-old-way-too-fast illness... condition... Think Robin Williams in Jack, only less sappy.

He runs really fast, like The Flash, thanks to their shared ability to tap into the energy of a parallel dimension. The Speed Force, as it's called, gives the speedsters their magical going-fast reality bending powers, such as phasing through walls, time traveling, going way faster than the speed of light, etc. Whenever their speed should've had horrible consequences on their surroundings, they can just claim that the Speed Force bent physics so hush.

Quicksilver is a Marvel hero. There's no such thing as a magical Speed Force dimension in Marvel's cosmology. So Quicksilver is an awfully lot slower. And there's nothing to bend physics for him, so he slips, he falls and he gets bitch slapped a lot. He's really not that great. As such, MCU Quicksilver was a lot closer to his usual power level. Personality-wise, he's a freaking jerk. Impatient, cynical, all around unpleasant. Thankfully, he rarely holds a role sufficiently important to have him speak all that much.

As for reading recommendations... Well, the New 52 Flash series has great art and an engrossing story. For Quicksilver... I got no clue. He's usually in the Avengers series, though for a good decade now Marvel has been spawning Avengers spin-offs like mad and I've no clue where he's currently parked.