I have a flat screen TV that is frozen-Help!! Please!!?

I have a 36 inch flat screen TV the kind you can hang on the wall-mine is not hanging- it's made by Sharp it's about 2 years old-the power comes on & the screen is black & says "please wait" & it has said that for about 4 days now! We don't use this TV very much it's in our bedroom-my husband plays X-box on it most of the time - I have disconnected everything from the TV & even unplugged it but it still won't work! Help! Please! We payed $1,500 for this TV -it can't break!
I can't check settings-none of the buttons are working I tried to change channel & nothing -the remote won't do anything but turn TV on-