Oh good grief, you were trying to climb in the big ring? No wonder you weren't going anywhere.
Sounds like a cadence monitor would be a good investment for you. Unless you're in your bottom gear and have no choice, you really want to be above 55-60 rpm on the hills to spare your knees.
Among other things, if you're mashing the gears you're likely not pedaling very smoothly, so you are at a bit greater risk of tipping over when you get below 3 mph or so.
NY Biker, I've heard people say that before, but not while they were walking up said hill.

Your walking speed declines on a steep grade, as well...