If you'd rather think about a Registry edit before making a permanent commitment, export the associated Registry subkey to a BEFORE.REG file. (In regedit.exe, select Registry->Export Registry File while highlighting the subkey.  Type in BEFORE.REG as the file name and hit Save.)  Then make the desired edits.  To return to the original version, delete the subkey and then import the BEFORE.REG file.  (Select Registry->Import Registry File, select BEFORE.REG, and hit Open.)