I have not seen this problem before, but I'm working on a fresh install and the check-boxes to select components for placement (such as BSM's) are not there in the pull-down list. The same problem exists for updating and refreshing symbols. I can select/highlight the name of the symbol, but the viewer remains idle and cadence seems unaware that I'm trying to place parts, or that there are parts to be placed. Quickplace works fine though.
My guess would be that you have the Windows display setting at something other than the default 96 DPI
Try resetting the default system fonts.