What is a good monitoring software I can use?

I'm concerned that my two teenage boys are doing inappropriate things on the computer and would like a program to record what they do. I've heard of this Amac Keylogger(http://www.amackeylogger.com), but after reading some about it, not sure I want to install it, also, it's very expensive.

Are there any free programs that can:
-Record what keys are entered

If they can do other stuff too, I'm sure that that would be great.

[Nintendo_Gamer]

Two Good ones I found (Both free to use) are:


The Web Blocker (http://download.cnet.com/The-Web-Blocker/3000-2162_4-10920621.html)

Short description:
Parents, librarians, business owners, and anyone concerned about inappropriate and adult content on the Internet may want to check out The Web Blocker from Webstart Studios. TWB is freeware that lets you filter and block inappropriate content, monitor Internet use, and build customized Block Lists for various users, situations, and content.


BlackBox Security Monitor Express (http://download.cnet.com/BlackBox-Security-Monitor-Express/3000-2162_4-75328923.html)

Short description:
Scheming teenagers, wayward spouses, and other sneaky computer users sometimes inspire someone to keep an eye on them. BlackBox Security Monitor Express can do this task for you, keeping track of the Web sites, keywords, and text that are entered by each computer user. Whether or not you should be snooping is something we'll refrain from weighing in on; all we'll say is that this program works.


I hope it helps. Good Luck! :)