Right click and go to view. Then hit hide desktop icons. Or you can just arrange them onto one side based on category or alphabetical order.
If you know how to start it up, you're better than me. I can't even find the .exe file to open it. I'm a laughing stock.
But if you can't open Rainmeter, just go to the Start button and open it from the Programs list. It takes a few minutes to get used to, but it's pretty simple to use.
By the way, my desktop is clean too except the recycle bin. Rocketdock is a godsend for organizing folders and icons.