When I select an Album in the Desktop and Screensaver Preference Pane, I can't select the "Change picture" box, so here's my work around. Select the photos you want to use in iPhoto, either from an album or in the library, then click the Desktop button in the Toolbar at the bottom of iPhoto. That will bring up the preference pane and this time, you want to select the "iPhoto Selection" from the top section. Now you can specify how often you want to change the pictures and if you want them randomly.

I've heard of using tabs in Safari, but I can't seem to find them. What's going on?

Sadly, by default tabs are turned off in Safari as is pop up blocking. I suggest you enable these features right after starting up your Mac for the first time. To enable tabs, just go the the Safari menu>Preferences>Tabs. I just check the first box, but you can experiment with the options that fit you best. Don't forget to look at those keyboard shortcuts while you are there.

Now you can start hitting cmd-T for a new tab or select it from the File menu. One great trick is to open a whole folder of bookmarks in one click by selecting the "Open in Tabs" from the bottom of a list of bookmarks.

That's no problem to do for it's just a setting to check off, although it only works in Icon View. Open your folder and make sure you are in Icon View. Then go to the View menu and select Show View Options… About half way down, check the box that says, "Show icon preview." You might also want to decide here to check the button at the top for whether you want this to be system wide or just in this folder.