Dpg
The options for using the wood behind the hole are good as well, I would not open the hole to the studs, you still have to tape those joints which will build you past the face of the existing wall, those would be butt joints and I have seen pros than cannot get a butt joint to look right. If you are going to go with either of these two methods, you need to create a v-channel at your joints, fill with durabond and then tape coat over that, otherwise you will have to feather out your tape joint in order to blend it. Do not just mud the seam without taping it, it will crack the first time something hits it.
You never said anything about wall paper, that makes things far more interesting, best bet is to attempt to remove the panel of paper that the hole is in, hopefully you can find a replacement. The other option would be to remove the pieces of paper of the broken sheetrock and try and glue the puzzle back together, either way alot of work. Other than I think a nice wainscotting would look nice in that room.
Not a real wallpaper expert, maybe someone will have something for you.
The new formulations of durabond are all sandable, durabond against joint compound will always sand harder, its a harder finished product. The 45, 90 and 120 represents time to fully cure. They are all the same product just formulated to dry at different rates, 45 or 90 is typically used for tape coat or repair work (no sagging and keeps tape nice and clean) and I have not seen anyone use 120 for anything.
Dan,
I have no idea why they call it a "california patch", maybe its all those flipped homes out there that have alot of holes in the walls and flippers are looking to go as cheap as possible, who knows.
