I too own a 1st gen iPad. I use it ever day. I don't update. You don't need to....Mine still works fine and I love it. I upgraded my iPhone 4s to OS6 and have had no issues. So my iPad has outdated software and my iPhone has the newest. They talk to each other. Try reverting back to an older OS. Also go in and have an apple geek analyze your iPad. Twice now I've had issues with slow response that were resolved through an apple analysis. Just make sure you have everything backed up.
