What's up with these weird colors?

Ok, well i have a dell inspiron mini netbook. I have the nickelodeon version if that matters. Since it is nickelodeon themed, it came with a nick them on the inside as well. Nick slime, spongebob stuff, things like that. And, it also came with the option to turn it to a normal theme if you wanted. so i did. I changed it back to a regular windows like, chrome colored theme. It has been on this theme since a week after i got this computer and, i got this laptop like, 2 years ago! the thing is, the theme is all fuzzy. Like, all the colors are all jumbled up. It's just a bunch of fuzz. If you think you know what im talking about, i can email you a screen shot, But does anyone know how to fix this? I have tried everything, reseting the theme, restarting my computer, everything. I need a tech expert