Disney California Adventure is the second park in Disneyland. California Adventure opened in 2001. Before then it was the main parking lot. When it first opened it only had a few rides. It wasn't very popular wit Disney goers. In 2012 Disney open Buena Vista Street and Carsland. After this was done it became popular with Disney goers.
The popular rides there are Radiator Springs Racers in Carsland, Toy Story Mania and California Screaming in Paradise Pier, Soaring in Condor Flats and Tower of Terror in Hollywood land.
In the morning they would open the gates a hour before rope drop. People like to stand over be Carthey Circle Restaurant. This is the start of the line to get Fast Pass for Radiator Spring. This line can get very long. It well snake though Hollywoodland. So if you want to get a Fast Pass for Radiator Springs you have to get there very early. Within a couple hours the Passes can be gone. I have heard that people that hold Annual Passes will go there get a fast Pass will get a Fast Pass then go to work, school or where ever. This area can get very crazy so if you don't want a Fast Pass stand clear of this area. The popular areas that people go to first thing after rope drop are Paradise Pier and Carsland. Many are going to Radiator Springs Racers and if you are going that way you better walk fast or you will be run over. Also people are heading over to Toy Story Mania. This ride is like a big Shooting Gallery ride. I know of people that have ridden it many times to get a High Score. There are many videos on YouTube on how to score on Toy Story. The line can get long but it does go fast. This is one of my favorites and when I go there I have stood in line for 20-30 minutes.
Radiator Springs Racers is another very popular ride. The lines can get very long. I have seen the Stand By line as long as 120 minutes. When it first opened they had to keep the park open until 2 am to let everyone ride it. RSR does have a Single Riders line. This line does go fast. Just as other Single Rider ride they follow the same rules. If they have empty seats they will get someone from the Single line.
These rides can break down at any time. Toy Story can be down first thing in the morning, but if you check back within a half hour or so it could be up.
Radiator Spring breaks down A LOT. It could be down for hours or be down all day.