questions about firefox 3.6.2and Kubuntu Security

I am sorry if I am asking dumb questions but I just installed Kubuntu yesterday .
Today I found out that firefox is 3.5.8.I looked at the repositories but Firefox 3.6.2 is not there.I can not update firefox.Since I am new to Linux I do not want to mess up.Is there an easy way to update Firefox? Or should I wait till it is in the repositories.
I would also like to learn the basic security precautions for Kubuntu.I am behind a NAT Router and I managed to use OpenDNS today.Do I need a firewall or antivirus or anything else.I do not want to be hit by a virus before I learn the basics of Linux.Also I can see the contents of the WindowsXP and the data partition from here(I found out while I was playing music in Amarok that I can play windows files).So if Linux is hit by a virus I can loose my WindowsXP.Is there a way to prevent this?
Thanks in advance.

 

In Kubuntu, click on Applications, Systems, and then scroll down to right-click on KPackageKit to add it to your Kbutton panel - then execute it by clicking on the icon.

You need to first reload the repositories, then search for Firefox by name. I use Ubuntu and Synaptic Package Manager, and it appears there are even 3.7 versions of Firefox available - however, my /etc/apt/sources.list is expanded from the original to allow for many other available packages in the repositories. One thing you might do before the above is to edit out the '#' comment sign at the start of the original /etc/apt/sources.list file by using the commands from a Terminal window;
ubuntu@ubuntu:~$ cd /etc/apt
ubuntu@ubuntu:~$ sudoedit sources.list

Note: Follow keystroke help at bottom of window, and then save the file after removing the '#' character on the lines that are not comments. Then reload the repositories and search by name for just Firefox which hopefully finds version 3.6.2 by now.

I am behind a NAT router also, but I have stealthed its ports and modified the ISP's DNS defaults to OpenDNS servers for both the primary and secondary. I also have a small script that initializes iptables rules on my computer - it drops anything that is not requested. You can find it here - use the Beginners edition link at the bottom of the post. Note: I normally power up my router after I have run the firewall script.

-- Tom

 

Thanks I added ubuntuzilla package from SourceForge net and installed firefox 3.6.2