Mac... doesn't have... double click?
Okay, I think you're looking for
right-click. And yes, Macs do have it, as long as you get a real mouse and not one of those stupid overpriced Apple mice. I recommend an inexpensive Kensington like
this one, for example, but there are plenty of brands that make Mac-compatible mice.
If you are stuck with a one-button mouse, simply hold the Control key and click on something to get a menu with more options.
There's also an option in System Preferences (aka Control Panel in windows language) that lets you set your desktop to cycle through all the images in a folder you specify, at a speed you specify (15 or 30 seconds at minimum, every time you boot at maximum).