Dell Vostro 1220 Laptop sometimes won't boot and display drops in and out.

Hi,
As the title says.. sometimes won't boot. I have managed to get it to boot sometimes by holding function key and "power".. Then I got it to boot just now by running LCD BIST.. but the display is unstable.. Whenever I touch the screen the display drops out and comes back and also starts to frost over and then if I touch it it comes back again etc. Where the screen is attached to the computer it feels a bit loose on the right side.. Is it time to get a new screen or tighten the screen somehow? Or is it the hard drive that is faulty or windows?
Thanks