What cannot start is not a threat...

I just want to know your opinion about this:

• Set "security" only for read in registers (HKCU\software..\RUN, RUNONCE) and (HKLM\software..\RUN, RUNONCE).
• Block the use of windows explorer for internet browse(use firefox, opera...)
• Turn off file share and printer share in net config(where the fixed ip is set).
• Turn off ICMP.
• Only let to log as an user (not administrator).
• Have a quite good antivirus program(avast, nod, avg...)
• Use any kind of firewall properly set(kerio, zone, sygate, isafer...)
• Screensaver and other such type of software set to block.
• Turn off some services...
• Alternative for ICQ and for outlook.
• Some antispyware software
• Teach not to click on any "unknown" links.

Is it enough for a computer protection?

I am "building"a computer for my cousin(16) and I think, that is enough for her safe browsing.