help MBP

Hi all after using my MBP from december 2010 i think my display is to small.. i bought a miniport display to hmdi cable and connected it to my TV.. im going to use the MBP for like a PC but using a external monitor ( TV ) keyboard and mouse.. the following problems are

When i open youtube i cannot see video's on my TV + external keyboard not working.. ( when i connect the keyboard the lights of the keyboard are going ON AND OFF.. after not working anymore.. any1 knows how to fix ?