How can inprove my sales?

I have a pizza restaurant and lately I have seen my profits diminishing tremendously.
I've been in business for over 30 years in the same place, used to have excellent sales, but...now, I can't compete with this big chains (McDonalds, Boston Market, Chilis, Olive Garden, KFC, Taco Bell, Salad Works, etc) which all are no more than 3 blocks away.
I'm to the point that I'm thinking that is better to close it, but I don't know what would I do next.
I have increased my menu items, deliver menus around the neighborhood, I deliver and also
increased the area of service.
Please help...need new ideas.

Never owned a retail location, but you asked for ideas.
1. Scale back the menu and stick with only those items that have been consistent sellers. 30 years means that you have a specialty people love, find it.
2. Stop trying to compete with the big chains and look at how they are specializing. KFC is known for Chicken; Boston Market for rotissere chicken; Olive Garden for their salads. They aren't competing with each other, and neither should you. What's your specialty that no one else has?
3. How has the neighborhood changed since you opened? It seems if the fast food chains are moving in, the people in the neighborhood has changed. Take a walk around and see who your new customers are.
4. Which chain is focusing on the customers you want? I do not eat at fast food restaurants, but I do eat out at Olive Garden and when I'm rushed for time after work, pick up a fresh roasted chicken from Boston Market. What does that tell you about me? I'm not a teenager, have discretionary income and likely a two wage earner household, i.e. we both work all day.

Hope this gives you some ideas to reinvent your restaurant. Maybe you have more college students around, or more young families with small children. The best way to scope out the competition is to go where they are - 3 blocks away. At lunch time, a Friday or Saturday night and even mid-week. It's a start to reinventing your business. Maybe you'll decide it doesn't need to be a restaurant anymore, and scale it back to become an after hours eatery.