Yes, janzman, as long as you have the expired one. You will need a new set of photos. Pick up the form from a Post Office and check the notes before you start- the guidelines for your photos have changed quite a lot since you last had one....alternatively you can renew online on their website..but as you have to send your old expired passport and new photos back to them, I would just get the application form.....fill it in, with appropriate payment, old passport etc.....and send Royal Mail signed for or Special Delivery guaranteed.
The Post Office offer a service to 'check and send' which is not expensive, so is an option, where once you've filled in form they will see that is fine correctly with the appropriate accompanying items, such as cheque, old passport etc and send it to The Passport Office for you.