The Speaker serves for the term unless he resigns or dies, although I suppose some rule change could be moved and passed. That would be a bloody mess, though.
Can some of the votes come from the minority party?
Yes, they all vote. The last time it was anything but a party-line vote was Jim Traficant voting for Hastert in 1990.
Well, if there is any way that a majority of the House could force a vote for speaker then there is a certain way to remove Boner.
1-Tea Party members let it be known they will not vote for Boner.
2-The Dems all vote for Pelosi and with the Tea Party guys refusing to vote for Boner she becomes Speaker.
3-Tea Party members announce they will now vote unanimously for a qualified conservative for Speaker.
4-A new vote for Speaker is forced and the GOPe members can either vote for the new conservative choice or suffer along with Pelosi at the helm.
This all depends on whether or not a majority can by hook or crook force a new election for Speaker.