1. What does realism mean to you? & 2. Einstein said:..
It depends. If you mean the 'physics' definition, or more toward 'the idea of what is real'?---When you even look around the web, there are various definitions by various people of the physics definition; and it seems every discipline (philosophy, math, etc.) uses the term 'realism'. 'Realism' to me is what appears real and logical --the moon will be there, even if I'm not looking at it. However, I don't think anyone will convince me that if one of a paired electron if rotated, that its 'other' one of the pair will rotate a light year away, or even a foot away. My logic will be different than any one else's logic--it's based on what I have come to believe. MWI is not logical to me, and neither is time travel.
3. In your opinion, is "realism" an assumption of Bell's Theorem? If so, where does it arise?
To me, it is an assumption based on an assumption.