Step 1: Look at your dock (the bit at the bottom of the screen) and play about - opening them up and seeing what they do - explore. The important thing to remember is you won't break anything by doing that.
I was new to Macs a year and half ago - I thought "I have no idea what I want it to do", and was scared of Garageband, iMovie etc. Now I use all the iLife apps and can't think of life without them.
What Mac did you get out of nosey interest?