Weekends are more crowded than weekdays at this point, as most LA area schools remain in session. That said, if you are ready to go when the park opens, I find that I can hit all the best rides at Knott's by early afternoon, even on a weekend.
On a Sunday, I would take the 91 to the 110. If you have two or more people in the car, use the carpool lanes. There's nasty construction on the 5 around the Knott Blvd exit.
First off, during our stay, a friend of ours parked in the hotel parking lot with no problem. Just don't keep your car there overnight unless you are with the hotel.
As far as the best day to go, anyday works according to my quick plan as long as you can get there 30 minutes from opening. Please tell me if you can on any of the days and then I can tell you how to get the park done (quickly) in 2-3 hours.
Well, here is what you REALLY REALLY need to consider that you can stretch out over anytime,as I know what time certain rides will open in the day and what areas the crowds are attracted to at which times.
Also remember this plan does not have to be rushed, and has been used affectively four days in a row, testing it on smaller crowds Thursday and Monday, and the larger ones Friday, Saturday, and Sunday.
So, when you get there before opening, the big surprise is that Ghost Town opens 10 minutes before the rest of the park. Once you take a first ride on Ghost Rider, leave for Silver Bullet. When you get there, you should be able to beat the crowds just coming in once the ropes are let down. Ride Silver Bullet and then head for Supreme Scream.
You will most likely notice Xcelerator start making test runs. Anyway, after Supreme Scream, either ride Xcelerator if it is open after its morning test runs, or head to Perilous Plunge and then come back to ride Xcelerator.
Now, head right for the Log Flume which will have just opened by now. Next, head for Bigfoot Rapids, barely beating the crowds coming in to cool off the heat, followed by Pony Express.
After this, any other coasters or rides are ones that always seem to have shorter lines (Montezooma's Revenge, Sierra Sidewinder, Jaguar)
Just make sure not to miss Mystery Lodge which is an amazing show with mystifying special effects leaving you to wonder, "how did they do that?"
And thanks for that tour plan, Nick. Spot on. Great advice there. All I'd add would be that if you can get the front seat on Silver Bullet without too much of an extra wait by arriving early, go for it. Inverted coasters are much, much better when you can see what's coming, instead of having your view blocked by the seats ahead.