If you want an AntiVirus for backtrack you shouldn't be using this distribution. It's a harsh truth, but you obviously do not know what you are doing.
Now that I've taken the time to read your other posts, I know for a fact that you do not know what you are doing.
Learn Linux first, sign up for an account on the Ubuntu forums. Install Ubuntu. Learn it, live it, love it.
Once you've spent a few months with Ubuntu and can do the following, then you can take a look at coming back to Backtrack*
- Determine which port a USB device is plugged into
- Create an alias IP address on a wired interface via 'ifconfig'
- Produce a list of the 2nd field of items in /etc/passwd using awk
- Create a ppp connection from the command line
The items are a little random, but they are a brief way of making you get a broader knowledge of basic linux commands and operations.
Along the way you will pick up answers to questions you hadn't yet asked.
*Note: This is all the opinion of one person and does not in any way reflect the team at offsec or the official position of the moderators