It sounds like physical screen damage, which will only be covered if you have Complete Care.

A standard warranty doesn't cover a cracked LCD, which is what this sounds like. Call Dell, but expect to be told the replacement screen is your bill.

You might as well just buy another computer, and might I suggest a different brand? I had my inspiron 1525 for a week, used it three times and never damaged it in any way and my screen developed an internal crack which they told me would cost $400 to repair on my new $800 laptop. Needless to say I am rather reluctant to spend that kind of money to repair damage that never occurred when I have never in my life had a laptop worked on and I have 4 of them! I bought this one to replace a 4 year old Toshiba which I am now using again since my Dell is ruined. They are not good computers, my research has shown that they have a lot of screen problems on their laptops and their customer service is no help either. MacBook's are great computers if you don't have to have a PC and their customer service and employees are phenomenal and as helpful as can be. If you have to have a PC and don't want to spend a lot of money Toshiba's are good, and Sony's are really good but cost a little more. If you have any luck with that screen issue definitely let me know how you did it because I'm getting ready to just recycle my week-old computer and start shopping for another one.