Trish - I like the For Dummies books because they are so easy to understand.
My advice would be to pay down debt while building an emergency fund. This way you are building a reserve of money for future needs that can help you avoid creating more debt.
Plus, if you are paying off credit cards, you are getting rid of a high interest rate. Credit card rates are impossibly high. Any investment you make would not produce as high a return so it's better to pay off the high interest debt.
Now I'm not counting the mortgage in this debt paydown. Obviously, that will take a while to pay. So you might as well go ahead and start investing.
Once you build up a reserve fund (say 3 months of expenses) then I recommend starting to put money into investments (preferably a 401k or Roth Ira).