My kindle 3 has frrozen

My kindle 3 model D00901 froze one morning after use. Page 1 shows whatever I downloaded, and over that is a rectangle with information starting with Turn Wireless on. My cursor will not move. I tried (more than 1 time) moving the power switch to the right. The green light goes on, flashes and then goes off. I continue to hold for at least 30 seconds, and absolutely nothing happens. The screen never goes off. I have had my kindle for several years and enjoy using it.