Yes, that is a nice drive, it's actually 40 to 55 north of Malibu as far as I recall. It just depends on the area. As far as driving up from LAX I would suggest you skip that. Do see all the things that the other posters suggested but I would take the PCH South from Monterey area instead. This way you have the scenery on your left and are not looking over cars to see the ocean. Also more people will be doing the same thing going south, and you won't be as pressed by some of the Wonderful California Drivers. That is the best way to do the PCH in my mind. Make sure you start early enough to make it though and see the sun set. Otherwise, you waste a good opportunity to see the seacoast in all it's beauty. Driving the PCH after the sun sets is not so exciting. Or maybe too exciting for some.
If you are set on taking the PCH to Montery I would suggst just taking the 5 N up to Paso Robles then getting on the PCH/101 then. Then consider taking it South on the way back. This is a good plan because it gives you a taste of the timing you are up against on the way back.
The last time I took the trip up noth this is how I went. It was a lot of fun, and is a very fun way to see what Cali has to offer:
Go up from LAX to Sequoia National Park. It is quite a bit inland but it's a nice trip and once you get on the 99 and 198 you drive through Orange Groves and things that are "Very California" Oh and Do stop at the gas station with the Farmers Market on the 99 they have awesome Pistachios. So You should be able to get to Sequoia easily in a 4 hours. So plan on having some time the following day to check the park out. Then you can take a drive up and over to Monterey at night and not feel like you are missing out on any scenery taking the regular highway. That should take close to 4 hours to get to Monterey so plan accordingly.
One more suggestion that you MUST follow. Before you get on the 101 fill your car up with gas!!!! 100% full. No exceptions!!! Don't do what I did and start running out and have to pay 6 a gallon in Paso Robles....or where ever that was. It was 6 a gallon!!!! So plan better than me.