In nero, select burn from image and select the bt3 iso. The default settings will make it bootable. Just remember to burn at lowest speed possible.
Depends on what you want to update. Look into: Fast-track, slapt-get. This link should help you well.
http://www.google.com/coop/cse?cx=00...%3Avpdhc1qej9k
Snort is an IDS. It is normally set up passively in a network to detect attack's on all of the hosts. Not the system it is running on. But I myself have not that much experience in the whole IDS topic.
Yes, they can. But not remotely without hacking into your system.
There are anti viruses made for Linux, but how necessary they are is a whole different question.... Read this
IPTables is a firewall built into the Linux kernel that you way want to look into.
The virus will most likely not work as 99,9% of the time it will be written for Windows, but the website may be attacking a vulnerability in for example flash, that your browser in Linux will most likely also be using.
A very hard way to learn Linux would probably be by using BackTrack. I would recommend starting out with Ubuntu and learning how to operate Linux. After that try Slackware (: . Try reading this thread: http://forums.remote-exploit.org/showthread.php?t=7180



