I have an interior door that semi-closes after each time you try to open it. The bottom of the door must have been previously planned quite a bit because it makes no contact with the carpet and will not stay open. It's a pain when we're constantly walking through the door and have to open it again each time. Is there a quick fix for this?

Take out the middle hinge pin, lay it on a concrete floor and smack it in the center with a hammer. Reinstall the pin, the door will now have mre resistance to opening/closing by itself.

I think you are talking about hinges being out of plumb. They should be perefectly vertical to each other, directly above/below. To test use a plumb line from the top hinge to the bottom. If they do not line up your door frame can be un-nailed and reinstalled prperly. This could cause you to mess up some of your trim unless you pry it very carefully.