Some good suggestions here, but unless you are working for one of the Government alphabet agencies (FBI, CIA, NCIS, DIA, ATF, HS, NSA)and there is work-related stuff on your laptop, I would strongly advise you against using any kind of disk encryption, regardless of whether it's Microsoft (bitlocker) or 3rd party software.
So, unless you are going to be keeping your kid out of criminal stuff that's on your laptop, or some other stuff on there that you shouldn't have, in my opinion disk encryption is a total overkill for the average home user.
Bear in mind the other guys recommending you to use disk encryption have advanced business IT experience and use this sort of stuff regularly to protect their companies or business Customer's from things like Industrial Espionage. Unless you are using your laptop to login to a network at your office or university, and that information is proprietary, again, a waste of time. We don't know exactly what you have on your laptop, and whether or not you really have these above discussed needs for advanced IT-level protection, but if you do, you may want to hire a Computer Pro or a Tech at your work or University to install Disk Encyrption for you. As Mike and other said, it's
CRITICAL you have everything backed up on that laptop
BEFORE you attempt Disk Encryption, as well as a Disk Image Backup File; as if you make one wrong mistake during the installation, your stuff is all locked up and you'll be unable to access it
FOREVER! Unless you are willing to pay
BIG BUCKS for forensic data recovery which costs in the hundreds to thousands of dollars.
These are some things to think about.
And, if that wasn't enough to scare you off; no one mentioned you need to make
CERTAIN that you remove any and all external removable storage devices if you do decide to install your own Disk Encryption, such as external USB hard drives, or flash/thumb drives. Again, average folks trying to use this don't realize that if they have 1 or more backup drives connected to their laptop and they install encryption it's very easy to check or forget to uncheck any external drives, and now
ALL YOUR EXTERNAL BACKUP DEVICES ARE FULLY ENCRYPTED--IF YOU LOSE THAT KEY, ALL YOUR STUFF IS GONE FOREVER!!
Well, if those arguments didn't dissuade you, I give up.
Food for thought before you jump into Disk Encryption.
<<<<BBJ>>>>