block access to safe mode for standard user

A much better solution MIGHT be to have a sit down with the kids:
"...any further action to disable my [meaning parents' control] filters will result in NO computer access for X days, understand?" ...and you gently but firmly follow through with such consequences.
And, during this discussion, let them know from news facts and stories of what can happen to computers, user accounts, program operations, data folders and files -- when filters are disabled.
I know of no way to do as you posted without you spending business-level funds for a business-level computer program.

I must say I agree with Roland on this one. But who are we to give family advice. So on to the topic at hand. there a number of ways you can disable Safe Mode. MSCONFIG is a non-option as your young savvy hackers will figure that out quick. There is a application that can block selected users from accessing Safe Mode. Watch the video to see how it works. "The Easy Way"----> NoSafeMode And then there is going into the registry and creating a Hack! "The Hard Way"---> Editing the Windows Vista, 7 and 8 Registry There you go! Hope this helps.

Lance, although this is a Windows 7 forum, I believe there is a family question behind the technical question. Kids will be able to defeat anything any parent can do -- without a business level program that totally locks out certain operations. So, I was hoping to give an answer to the inner question, the family question -- because in the long run, once the kids buy into the very good reasons for the parental controls, once they are with "the program" -- the technicals will take care of themselves.

Although I have never been a parent, I have been around a mom with two sons for eight years long ago, and I have been a substitute teacher for three ISDs for almost 8 years, so I have picked up a few things that may work for some and not work for others :)