The default location for your converted files is in Movies > Smart Converter Pro 2.
To change this click the Set Destination button on the Smart Converter Pro 2 window. Navigate to the folder you would like to be the new output destination and click open.
That's it. Your conversions will now go into this new location.
Extra Tip: If you forget what your output destination is set to, click on the action button (the down arrow pointing to a circle) immediately to the right of the Set Destination button. This will open the folder of your current output destination.