Another layer of drywall might help reduce noise. Wood paneling will add nothing. If there is NO insulation in your exterior walls, then yeah, you need to do something to rectify that. Blown in insulation seems the way to go. BUT, blown in makes a BIG-TIME mess when you blow in from inside the house. If you are prepared to move everything out of the outside wall rooms and shop vac yourself to death, then you'll be fine. Check your walls for fire breaks before you start. Fire breaks are blocks from stud to stud about half way up from the floor to the ceiling. If you have them, then blow in insulation will be twice as hard to work with. If you have the option to blow in from outside, this is the preferred method. Especially if you have vinyl siding. pop one piece loose all the way around the area to be insulated. Plug the holes with whatever you can find that's solid enough to get a good seal and put the siding back over it. You should be able to rent the machine for half of a day after you get the prep done. Spend a half day closing it all back up. Total estimated time,,1 day to 1 1/2. Ladder work will slow you down if you are insulating an upper level. There have been folks that have just found it easier to pull the drywall off and insulate with fiberglass batts. Consider how much repair will be required and decide wich way to go from there. If you do rip the drywall off, the best noise cancelling material I know of is the old black tar fiber board. Cover the wall with that stuff and then cover that with 1/2" drywall with screws. When I've been involved in commercial jobs with closed session conference rooms, that was the standard architect's noise barrier. Ripping the drywall off also gives you an opportunity to get a vapor barrier in the wall.
Sorry about the wait. If someone else posted after you did in the same department, I may have just not seen you're question. I also *sometimes* try to give someone else a chance to answer the questions. I think all of the regulars recognize me as a long winded know-it-all.,, InspectorD, am I right?
Tom in KY, not a PHD. More like a BSd.