Dock related problems

I have no clue how to describe my problem so i will try my best.
Ever since my dad set some parental controls on my mac mini running 10.5.8 My dock only shows Finder, my applications and the shared folder. I cannot put anything on my desktop or the dock.Programs i downloaded off the internet would not show up on the dock or anywhere else where i can easily access it, like it used to before my dad set the parental controls. The only way i can find my program is that i use the find function in the finder.
Can someone please help me so that i can reset the dock back to its original state. I also don't have the file com.apple.dock.plist if thats relevant

i've tried looking for it via users>library>preferences and used the find function but still could not find it. But i do have a file called com.apple.dockfixup.plist but i don't want to mess with any files that i do not recognize which would be just about all of them.