what stwert said

btw, are you actually in vertex selection mode? (i dont' have maya in front of me so i can't see what happens to the icons at the top)

hold down right click without holding any keys and then select vertex

also... on an offtopic note
see on the left there there is that little black arrow?
click that and there should be an option to show the shelf's tabs so then you get a whole lot of tabs above your shelf and it makes it easier to change between shelves.
i would screen shot you but as i said, i dont have maya in front of me, the option might also be in the display menu of the program