There are several more post in the forums about double clicking and changing the double click speed. Some have the answers, but most don't offer many details. For the record, single click/double click is controlled by Rox and the speed is controlled by GTK. So, if you want to change to double click here are the details:
To set double-click:
-open Rox filer
-right click in an empty space in the filer window
-click Options
-click Filer windows
-uncheck Single-click Navigation
-click Pinboard
-uncheck Single-click to open
-click OK
To adjust double-click speed:
-open the Geany editor
-click File/Open
-click root in the Places window
-click Show hidden files in the lower left of the window (will be under More Options in newer versions)
-scroll down and click the file: .gtkrc-2.0 in the Name window
-click the Open button
Add this line to the bottom of the file: gtk-double-click-time = 500
-click File/Save
-reboot for changes to take effect
You can adjust the 500 number up or down to change the speed, reboot between changes
Credit for these solutions belongs to others who have posted, I have just filled in details of how to click through it.