How do I remove molding with out damaging the molding or the wall?
(after slicing the paint/caulk seam...) A wooden shingle slid behind a small prybar (http://www.hardwareworld.com/SharkGrip-Prybar-~-8-pGJXJX8.aspx) is ideal. 

It also helps to find the studs and use the prybar over them because 
   1) that's where the nails in the molding are most likely to be, and hence lessen the chance of damaging the trim
   2) the sheetrock will be less likely to break in those places as well. 

There's also often a sort of order that it is installed, and is most easily removed in the reverse order. So take a look at which way the pieces overlap at mitered seams.