Need advice regarding painting.

[jeff47]

8. It's a small moulding

What makes it crown moulding is where you stick it on the wall, not the shape.

Top of wall and onto the ceiling - crown moulding
Top of wall and not on ceiling - frieze (This almost always has crown molding above it)
Middle of wall, about 3 feet off the floor - chair rail
Bottom of wall and over the floor - baseboard

Then there's a name for the individual shapes commonly used for the moulding in each location. Cove crown moulding looks like this.

The location is actually important - there's another kind of cove moulding meant to be baseboard. It looks like this.

If you go with the moulding, another poster mentioned the problem of uneven walls. The moulding is straight. The walls and ceiling probably aren't. The way you solve that problem is with acrylic caulk. It will stretch as the moulding expands and contracts with humidity. Run the caulking along the bottom and top of the moulding to fill the gap, and then use a putty knife covered with a damp rag to make it flat. The idea is to make it look like you shaped the back of the crown moulding so that it fit the wobbles in the wall and ceiling.

Note that you should not use silicone caulking for this, or any other caulking meant to seal against water. You want the stuff in the paint aisle that's only good for filling holes and gaps before painting.

And if you do go with some sort of crown moulding, you will have to paint it too. But the sharp transition of the moulding helps to hide imperfections in the transition between the wall, moulding and ceiling because of all the shadows created by the moulding.