Hello,
I'm putting in a tub surround in which panels are glued to the wall. I wonder if I can just clean out the existing grouting and tile and glue the panels on top of the tile... this would eliminate having to take all the tile off which would leave the wallboard ripped up with old mortar on it. I figure the tile would be a better surface if its going to work..... WHAT do you think?

Is there a problem with the tiles? Has water gotten behind the tiles? If yes, then the tiles should be removed and the green board (not regular drywall) should be repaired.