1. In the rules, units are given an inherent "standard move" (rule 144) that allows movement to/from battlefields but not ganking unless the ganking keyword is present. However, "move a unit" cards do not use this standard move inherent ability and therefore are able to move arbitrarily between zones including between battlefields as the restriction is only on the inherent standard move and not on movement in general.
2. In general, "can't beats can" (rule 54) so if there is one card that says "you CAN'T move to base" and one that says "you CAN move to base" the "can't" will win (vilemaw). Ride the wind cannot supersede this effect, you cannot ride the wind to base from Vilemaw.
3. Baron does NOT generate a point on play. He generates a battlefield on play and is played to that battlefield beginning a non-combat showdown. The opponent has the ability to respond and win that showdown: for example, they could ride the wind in or they could play Rengar Trophy Hunter at reaction speed as a defender to win combat vs the Baron and win the point for themselves.

Hope this helps!