[expert] Need help Closing Open Ports

[Richard Yevchak]

I have disabled almost all services that listen to an outside port
like telnet and ftp.  When I port scan my computer, nmap shows I have a Printer
and an X11 port open.  I want to know if it is possible to disable these ports
as well.  I'm on the campus network and Port Sentry indicates that I've been
scanned.  I want to protect my system.  I'm not a print server and I really
don't want to use X remotely right now.  

Any help would be great.

Richard