First, you mentioned close to the boardwalk, so try Holiday Inn Suites or Quality Inn Boardwalk.
However, you do not need to be on the boards to be close to everything. OC offers a great bus system for travel, and there is so much to see and do all over OC that you never run out of things to do. So a few other hotel suggestions, Clarion, Carousel, Castle in the Sand, Princess Royale, Princess Bayside, Quality Inn Oceanfront. All of the mentioned hotels would have breakfast options.
There are several parks throughout OC, so check out
www.ococean.com and see which one is closest to your hotel.
One final point, August stays will require a minimum stay and since it is prime vacation time, I would suggest calling whichever hotel you choose as soon as possible so you can obtain the desired number of rooms.
Thank you,
Anna G.