iMac New

I'm on my new iMac.  It's my first Apple.  I downloaded Picasa 3.6.1 because it already has a bunch of my pictures and I unabashedly love Google.  I accidently  downloaded it 7 times.  Opps.  And there is no right click delete.  As you can see, there is a learning curve.  But in my defense I've actually looked at a couple of tutorials.   But not the ones on downloading and deleting.  And not the one on fixing photos.  Bear with me.