Changing permission of a folder
 

I am new to linux. I just installed an HLDS server for Counter-Strike. I followed a tutorial on how to do that, and it was set up in root. I want to know how I can unlock the folder so I can access it on my account. How can I do this? I'm running an HD install of KNOPPIX by the way.

Also how can I setup an FTP server to share that folder, so I can access it from my other computer.

To change the permissions on the folder, use the command chmod. The internet will tell you more in more detail and accuracy than I can how to use this command.

What's the purpose of the FTP access? If you only want to enable access for yourself, I would advise enabling the ssh daemon, and accessing things via sftp. If you need other people to be able to access it, FTP might be an option.

I wanted to access it from my other (Windows XP) computer. They're connected on the same network by the way.

switch to root user using "su"
chown -R <yourname>:<groupname> <directoryname> (groupname can be the same as yourname)
The -R causes it th make the same change to all the contents

then, as regular user <yourname> (or as root), you can change permissions using chmod

Remember to make all directories executable, otherwise you can't get into them

For more details:
man chown
man chmod