Casio Exilm Camera problem!?

So I bought my camera less than a year ago at Radio Shack, when I went back to let them know that 1. the USB cable was damaged, I also let them know that when I took my memory card to Costco, a lot of my pics had these weird color blocks on them. Most of which didn't show up on the preview but did when I uploaded them. Of course they take no responsiblity and want to take my camera for weeks at a time.... Has anyone else had that problem? I have the technical warranty on it.. but if it's user error (which could be) I'd like to know. Thanks!