Graphics issues with new iMac

I'm hoping someone out there can help me with this. My new iMac (In sig) is having random graphical issues. I posted pics because I don't really know how to describe them.

At first, I would just restart and the weird stuff would go away. Figured the graphics card was just tired from rendering video. But today, it happened again and when I restarted, this error came up. I'm sure they are not related, but still, it worries me that my iMac is acting like this.

Should I take it to the Apple store? Or do you think a full OS restore would fix it? Do these look like signs of a deeper problem that could become worse over time?

Thanks in advance for your help!