I've changed from the default double-click to single-click for opening items in Explorer. The bad side-effect is that holding down shift and clicking doesn't select a row of stuff anymore. You have to deal with individual check marks.
What I'd like to see is a quick toggle, perhaps with a selectable hotkey, that changes between single and double click mode. So I can toggle to double-click mode, select a bunch of items using Shift click etc.., then when done, toggle back to Single-click mode.
Could be the best of both worlds. I know where the setting is in the Explorer menus but I don't know the registry keys that control it to attempt it myself.