and now, I an unable to pin programs to the taskbar (as they warned may happen). Is there any way to restore the registry to previous settings?
Reset the Registry? Not without reinstalling Windows. Assuming this is a very recent change, I suggest you look in System Restore and restore back in time to just before you made the change. That should "reset" the Registry, if you will, to the point before you dinked with it.
Then I might suggest you check out
Link Removed - Invalid URL. It has an option to remove the arrows, as well as the "Shortcut" suffix.
WARNING: Do backup your registry first - and if not sure what a setting does, don't do it!