Why do Cooper pairs not bump into other particles? I sort of get how they get formed and how it works but why do they not bump into other particles? and do the spins have to do with this?
 A: Spin indeed plays a role in this. Cooper pairs are bosonic in nature, below the critical temperature they condense into the same state to form a superfluid phase responsible for superconductivity. This is why they do not "bump into eachother", they are all in the same state.
Moreover, the condensation of Cooper pairs opens a gap in the excitation spectrum at low energies. This means that you need a finite amount of energy to break up a pair if a Cooper pair were to collide with something else inside the material. The energy gap $\Delta$ is of same order of magnitude as the critical temperature $T_c$, in a way you can think of the superconducting transition as thermal fluctuations breaking up Cooper pairs when you reach $T_c$.
Also keep in mind that electrons forming pairs can actually be very far away from eachother, say a few hundreds of nanometers. Thus many pairs can occupy the same space, they form a very rigid superfluid phase that moves in "one block" and does not get affected by defects or other particles.
