Ive been to WDW 5 times and
Disneyland probably about 30 times now.
One biggest piece of advice is dont expect Disneyland to be WDW. There are many of the same attractions there and to tell you the truth Disneyland does it all better with the exception of Tower of terror, winnie the pooh and a few smaller things I cant think of right now.
Disneyland is all in one little place. You never have to ride a bus (except from and to hotel if you are too far to walk). The two parks and downtown and all three Disney hotels are all walking distnace apart from each other. Grant it a long walk from the edge of Disneyland hotel to the edge of Disneyland park.
When you go to Disneyland let your impression be unique and not expecting the huge resort of WDW. Its Walts original park and you will see vegitation thats grown and mature. The weather is fantastic in California so the landscape and flowers and such are beatuiful and you wont beleive this but no humidity like Florida. I am from Arizona and I think California has some humidity but nothing like Florida.
Most of my disneyland trips are 2 days because I drive over for the weekend. I prefer the trips when I take a couple vacation days. In May we went 4 days and it was perfect to see and do everything I wanted many times. Im the type that likes to stop and see the things around me. I like time to stop and listen to band play on main street if I have time or watch a comedy show outside of Golden Horsehoe on the street. 4 days allows this.
My most notable cons of Disneyland are:
No Epcot. I love world showcase and there isnt anything like it at Disneyland.
Two parks not 4.
Only 3 disney hotels and nothing budget minded like All Stars. we always stay across the street because we can afford to go more that way. The Grand Californian is beautiful and reminds me of Wilderness lodge. The Disneyland hotel sort of reminds me of the Contemporary hotel and paradise pier actually reminds me more of a hotel you find near Down town disney like Grosvner or something like that.
The castle is small compared to WDW.
Most Notable Pros:
Way better small world, pirates, haunted mansion, Space mountain, and toon town, Plus an extra land - New Orleans Square
No buses to go from park to park.
The weather is way better
It's Walts park
I love Story Book canals. The little miniature trees are really old and I love how they made them into scenes.
The Hyperian Theater show Aladain. Its awesome! And the theater is beautiful inside too.