I absolutely hate the Haunted Mansion! LOL!
Weird! But I kind of envy it in a way... I'm a big Haunted Mansion fan and love it to death. I love the atmopshere of it, the gags, the characters... My girlfriend, on the other hand, is actually scared by it. In fact, she keeps hiding my Mansion stuff when she comes over because it creeps her out to see it! I would love to be able to experience the attraction in her way at least once.
As for things you can do, well, it's sort of personal based on what interests you. I can give you the list of things I make a point of doing (I would also mention that I live quite a ways from Disneyland, so I go for a week at a time)...
- Treat Main St. USA like its very own land, not just the mall you have to get through to get to the rides. Spend time in the Disney Gallery and The Disneyland Story (aka: the Great Moments with Mr. Lincoln preshow), look at the Emporium window displays, watch the street performances and cartoons in the Main St. Cinema, listen to the phone in the Market House and the ragtime piano at Coke Corner, and check out the remaining vintage machines in the Penny Arcade.
- Food is an intrinsic part of the Disneyland experience, and the ones I feel the strongest associations with are having a Dole Whip in the Enchanted Tiki Room and mint juleps aboard the Mark Twain Riverboat.
- You'll probably be in Disneyland 'till after close, but if you have the time, going for a bite to eat at Trader Sam's Enchanted Tiki Bar and then a nighttime stroll around the Disnyeland Hotel grounds and Downtown Disney is a wonderfully relaxing time.
- There's practically nobody back around Big Thunder Ranch during the day's peak hours. It's a nice escape and the goats are so cute!
- Speaking of Big Thunder Ranch, I've found that the Blue Bayou is overrated, but Big Thunder Ranch BBQ and the Plaza Inn were great.
- Since you're going in summer, it will be busy, so prioritize. Think about which rides you really want to go on and develop a strategy for taking on the day (for me, the Haunted Mansion is one of those rides that there would be no point in
going to Disneyland if it wasn't open... Other "musts" include Peter Pan's Flight, Enchanted Tiki Room, Jungle Cruise, and Indiana Jones, but I go for a week in the off season so that I can ride as many as possible as often as I want... I think the only ride we bypassed last time we went was Casey Jr.!)