I agree with Tightwad with regard to the mortgage. If the interest rate is low, it's cheap money and you can allocate the money you'd use to pre-pay your mortgage to beef up your retirement fund instead.
I also agree that you guys are pretty well situated. I think you'll probably need to do a bit of tweaking (most of us do), but won't need to do anything in the way of wholesale changes to what you've been doing for years.
As for retirement itself, check out
Transparent Investing. It has links (mostly to Vanguard) that will help you determine how much you need for retirement and what also help you determine your risk tolerance. It will also help you determine the appropriate asset allocation for your goals and how to allocate them between taxable and tax-deferred accounts. Have a look and do read the Full Story pdf file; it's more comprehensive than the 10 steps outlined on the site.
Welcome to the forums. Feel free to come back and ask questions.