Could you pleas describe the lines for us. Was the laptop stepped on or dropped? How old is the laptop, what is the model, etc? Are the lines always on the screen or are they only showing when the system has been on for a while. Does the system freeze when you see the lines?
If there are always lines on the screen and the system seemingly works fine otherwise, you will probably need to have the screen replaced. If you are in the Central Florida are, we can get a technician out to you to fix the screen for you. If you are not, we can help you get the screen installed.
If the lines are only showing when the laptop has been on for a while or only when it boots into Windows, this is probably a software problem and we can help you get that straightened out.