PARSIPPANY, N.J. — Kings Super Market here is scheduled to kick off an ad campaign today touting changes it has made throughout the 26-store chain. After testing new merchandising strategies that incorporate more high-end products and services and an expanded selection of everyday items in about half a dozen stores for the past several months, the company said it has implemented the strategy throughout the chain. It has also expanded its advertising circular to 16 pages or more and made improvements to the graphics. The chain is using the in-store promotional materials touting “Hot Prices — More Choices” and the tag line “From Everyday to Fabulous Gourmet, Expect the Unexpected.”