Walls and Ceilings - Inside joint repair-to tape or not to tape?

I've got a nearly ceiling to floor crack in a 45 degree inside corner joint in my dining room, and a crack nearly identical to it in the room over the dining room. The house is 2 years old, the crack hasn't gotten any worse in the last year, so I'm guessing it is a settlement crack. I'm wondering if I need to retape the joint, or if I can just remove the rough edges of the crack and use compound to even it out before painting. There's no visual evidence of sagging or damaged tape, at least not yet...maybe I'll se something different when I start removing the damaged material.
Thanks for any suggestions or opinions.

Depending on the crack if its just a hairline I would use a little latex calk on you finger and skim the surface just in the corner with it.;)

I'd agree with Homer if it's just a hairline crack, a little caulk & then you could repaint. But if the tape is actually coming loose, I'd pull the old tape off completely & retape & mud the corners. Good luck. ;)

Some places it's hairline, but most of it is not. Some areas have one side of the crack sort of warp up and away from the other, so I need to either sand it or chip it down, then build it back up evenly. Since it isn't crumbling, I'm wondering if just sanding it level then filling in the gap with mud will do the trick.

Where the crack is the worst, I still don't see evidence of the tape being involved, so I'm hoping it's just the mud that had cracked open.

From you description of the problem this morning, I think I would use an old 6" drywall knife to chip down the high spots and then I'd retape the corners using paper tape, followed by a couple coats of mud & you're ready to primer & paint.

Thanks, aeveryone, for your suggestions.
Awesome, can I put tape over the joint without removing the old tape? I've never done this before (you probably couldn't tell that, I bet) so I don't know how a proper tape job ought to come out, but it seems like that would cause a buildup in th ejoint and kind of roung it off, taking the angle out of it. The guy at the store sold me the mesh tape-will that work for this application?
Thaks again, you have been very helpful.

You can usually get under the old tape with a drywall blade & rip it off of there. It would be better to remove it if it will come off.

Yeah you can use the mesh tape, IMO it takes more mud to cover it than paper tape, but it's easier to deal with for alot of folks I guess.

Some times joints crack because there is too much mud over the tape. This happens in corners because it wasn't pre filled. Then when you tape you get a recess in your tape. Then you coat over it and get a build up of mud which cracks. Tap on the tape joint and see if there are any hollow sounding spots or loose stuff. If not then re tape over the crack. Good luck.