Disagree with family.

I'd say it depends. I think it's important to be yourself, but if what you disagree on is something trivial, then it may be better just to keep it to yourself, thereby avoiding a confrontation. On the other hand, if it's a big deal and it has actual consequences for you and/or your family, then you should probably go ahead and get your position out in the open. That way there won't be any surprises at inopportune times.

An example of a somewhat big deal in my case: my dad used to bug me to go to church with him whenever I was over at his place on the weekend, and I would shrug it off and say I didn't want to get up that early. Eventually, he started getting more and more pushy about it, and I ended up having to tell him that I stopped believing in his god in front of his wife and my little brother. I should have been honest with him to start with, but it's kind of difficult disappointing a parent, even if it's just by having a different opinion.

It was worth finally coming clean though. He stopped bugging me to go to church and he got over the whole thing eventually. The same could happen for you.

Jam it back in, in the dark.