It seems to be a somewhat intermittent occurrence, but looking at task manager processes, when I try to run either installer javaw.exe appears for a few seconds and then goes away. I have recently uninstalled minecraft, forge and both 32 and 64 bit java versions.
Edit-
I uninstalled the 64 bit java I had installed, and tried the windows forge installer executable again and it worked this time. So, not to self/anyone who cares... forge doesn't like to install with 64 bit java installed, or maybe with both 32 and 64 bit versions.