Hi.
I just port scanned my server,and saw a lot of open ports.The ports that were found open were:

Port 21 File Transfer Protocol [Control]
22 SSH Remote Login Protocol
25 Simple Mail Transfer
80 World Wide Web HTTP
110 Post Office Protocol
I'm extremely concerned about the security of my website.Therefore I want to close these ports.However I would be using the services that these ports provide most of the time,so I'm not sure if I want to close them.Or is it possible that I open them whenever I'm using their services and close them afterwards?If it helps,my host is running Unix,and it allows me to telnet to it using SSH.And,I've bought paid web hosting at WestHost.I use Putty to telnet to my host when needed.

Two more questions,when i noticed the port 25 open,I immediately tried sending an anonymous mail through Telnet.I'm sure most of you would be familiar with how to do that.and it WORKED! This is definitely not something I want.I'd like to disable it somehow.Like most of the other servers that throw up an error when you try to send anonymous mail through it.How do I do that?please keep in mind that I do want to be able to send and receive emails sent to any of my email addresses at my domain name.

Last question,I dont have a brute forcer right now,so I havent checked.But I want to put up a system that would automatically disconnect after 5 or 3 failed login attempts.I once tried to brute force a website that had this system set up and it always disconnected me after 5 failed login attempts.It was a real pain and I couldnt brute force their password.Now that I have my own server to administer,I think that is a really good idea.Any info on how I would do that?
i appreciate your help.
Ali.