The Brew Cabin

I have a patio which runs between my house and a retaining brick wall (12 feet x 30 feet). The 2x2 slabs are old and dirty and really beyond cleaning. I don't feel confident enough to lift them and re-lay new ones.

Any suggestions as to what could be done to revamp the existing slabs or make easy changes to the patio.
I have had a quote to deck over the top of the slabs but I'm not too sure about that!

Wash them down with a patio cleaner or brick cleaning acid and they should come up like new.Other than that, all I can suggest is ripping them up and starting again, or, if you can't face that, bring in a contractor.