A typical Linux desktop 

Everyday Linux

 an average computer user's getting started guide

Linux is a vibrant, thriving alternative to / replacement for Microsoft Windows, especially suitable as a replacement for expired / unpopular versions, e.g. XP / Vista. In everyday use it's much like using a good traditional version of Windows.

When it starts up there are program icons on the screen, click on an icon and the program opens, just like Windows.
You can add, or remove, programs and program icons to suit you. Quite possibly you'll notice it's faster to start up (and close down) than Windows, that's a bonus of using Linux.

There's the equivalent of the 'Start' button, although it will probably be labelled 'Menu' rather than 'Start'. Clicking the 'Start' button will bring up the various options. They won't be exactly the same options as your version of Windows but the idea is the same, exploring and using them is easy.

Next: The Linux advantage