Wirless Internet Suddenly Not Working -- HELP!!!

Hi everyone,

I have had a Dell Inspiron 1520 laptop for over a year and a half now.  I have never had a problem with my wireless internet until this week.  For the past few days, I will wake up in the morning and my internet will not be connected anymore.  The little symbol isn't even in the toolbar with the clock anymore and it just disappears.  I go to "Network Connections" to enable it and it says "Enable Failure!" just moments after starting the process.  Up until this morning, if I restarted my computer, the wireless internet would begin operating just fine again, but I was having to restart twice a day.

This morning I woke up and it was again not connected.  I restarted my computer and it showed the icon in the taskbar and that I was connected to my network with a "Very Good" connection.  However, none of my internet-dependent applications work.  My web pages don't load, AIM doesn't connect, and my MSN Messenger doesn't connect.  So basically my computer is showing that everything is connected but its not working.  I thought just for grins I would run MSN Messenger troubleshooter and it revealed that everything is working find EXCEPT it pulled up an error next to "DNS" and also next to "Key Ports."

Can anyone please help me??? I am good with the basic use of a computer but things like this I just don't even know where to begin, nonetheless can I afford to take it into the shop.  Any advice is MUCH appreciated!!!