I can almost guarantee you that you froze an app that is needed and that is what is causing your random rebooting. Nothing to be skeptical about because that usually is the issue from what many have seen.
Again, a list of what apps you froze could be helpful too. You definitely have to be careful freezing system apps as many other apps require the services they provide, including other system apps. That could be the issue, depending on what you froze.
Let us know how things turn out and a list of what you froze would help us identify your issue if that indeed is the problem.
If you really must freeze apps, I would suggest you go to this thread ->
http://xdaforums.com/showthread.php?t=2756195
People are listing what they've frozen that hasn't caused any issues.
Also, instead of freezing an app, again use the Greenify module. This ensure the apps never comes out of wakelock, but unlike freezing, if you need the app for some reason or another, you can just run it. As long as it's in the foreground running, Greenify leaves it alone. Once it no longer is in focus, Greenify will wait to see if it stays that way for a set period of time and then hibernates it, not allowing it to run again unless it's brought back to the foreground.
Freezing an app makes it unable to execute, which could cause issues if other apps depend on it.
