Welcome Thumper, Removing directories which have files/programs that are active is difficult but can be accomplished. Adobe has a couple of dll's that are loaded at startup time. If you have removed adobe via the installed programs removal process, then they could still be active.
One way would be to stop their process vial the manage option and services. you can stop the process and disable it. on reboot, it then would not be active and you should be able to delete it.
Normally the install of adobe x will remove the older adobe drivers
Outside of that, you can restart in safe mode and that SHOULD then allow you to remove the directories.