For new installed Windows 7,only Recycle Bin is showd on desktop,if you want to show My Computer on desktop.Please follow below steps.
Click Start ,in right pane ,right-click My Computer and select Show on Desktp
1.Right-click an empty place of you desktop and select Personalize
2.In the left pane,click Change Desktop Icons
3.Check the check-box of My Computer ,then clisk Apply ,then click OK