A couple of simple questions

I've used PS for years, and currently use CS4. I also use Lightroom 2.2, for the great convenient qualities it provides, BUT can someone please tell me how to minimize LR on the monitor screen, so other icons are visible?
I can't see how, and have to close LR to get to my screen.
Thanks

Press "f" one or two time to exit out of full-screen mode.

By the way, it would be to your advantage to update your LR to 2.6 (and the Camera Raw plug-in for CS4). This is easily done by using the Help/Updates utility in CS4 Bridge and the Help/Check for Updates in LR. Both LR and ACR issue updates around every three months or so to offer not only support for new cameras but also fixes and improvements "under the hood".