Can Bear Hug force a player to destroy an Incorporeal minion?
Bear Hug cannot destroy an Incorporeal Minion.
First to correct some termiology. Bear Hug is not played &quot;on a player,&quot; it is simply played. Cards that are played on something will use the word Attach, and to my knowledge no cards Attach to players. Secondly, the Bear Hug card is destroying the Minion, the instructions on the card informing you which Minions need to be destroyed (Each other player's, with the least Power). Players do not affect cards, because nothing in the rules says they do. Cards do affect other cards if they move, return, destroy, or attach to another card.
The rules state the following:

Affect: A card is affected if it is moved, returned, destroyed, or has an action attached. (pg 8)
If cards conflict, the one that says you can't do something beats the one that says you can. (pg 9)

Incorporeal prevents the attached Minion from being affected, so Bear Hug cannot affect (destroy) the Incorporeal Minion if it is played by an opponent.
This hasn't showed up in an official FAQ, but one of the designers, Mark Wootton, noted that Incorporeal protects a Minion from Poison.