Open A File It Will Just Hang There And Not Open?

if i go to the start button to go to my computer the window will open on the first try , but say i try to go to my computer again it will just sit there and not open. the exployer window will open but not the contents inside.does not care how many times i try it will only open the window and show nothing inside , a bar will go across the top to show progress but still it will not open.if i restart the computer i can open up the my computer or just computer in W7.like right now i tried to open up the window to check my hard drive and im still waiting for it to open.this goes on on both of my computers running windows 7.all coms are updated to the fullest and im not overclocking or doing anything other normal stuff.So is there a bug or somthing that im missing , once again if i go to start , and hit computer the window will open on the first try , but if i do it to many times it will just open a window and just sit there.even further if i open it up and try to open a file it will just hang there and not open , there is no error warning or nothing.