Iphone Lock Problem?

When my iphone auto-locks(or I lock it) and i press the home button to unlock it, it gives me a blank screen with lines. It happens almost all the time. I always have to do a reset to fix it. I did find a solution which is, playing music in the background when i lock it, but that drains the battery a lot especially by the end of the day. And when my iphone is connected to my comp., it has no problems at all. Can anyone find a way to solve this or give me some help/tips? i'm pretty sure it's a software problem. Thanks

iphone 2g 8gb

 

Yeah, im in desperate need of an upgrade haha. I found that using the Android OS on the iphone fixes the problem(s) so i might just keep using Android for now.