Backdoor IRC bot and backdoor SDbotGenerator. help!!!

Hi

I ran norton AV scan and spybot search & destroy over night and woke up to the results. I had 3 "backdoor irc bots" and one "backdoor SD bot gen."  Anti virus said they were found and deleated. I then ran "shields up" from a link on dslreports to see if there are any ports that were changed and found one port that was stealth changed to closed and responds to Icp ping. I have again done live update and full system scans to see if any came up. I came up clean according to results.  There may be something still in there sleeping or hidden. I havent downloaded anything recently and cant figure out where this stuff came from.   also scanned with "search & destroy and came up with 3 data miners where I know the origins. what can I do to fix that one port back to stealth instead of closed, and also remove anything else that might be a problem. maby a bot removal tool, where do I go and what do to restore confidence in my machine.

Thanks in advance, atla5

Inspiron 8100
Dual boot OS Red Hat 9, Windows XP Home, Pentium III 1.13GHz
60 GB 5200rpm HDD upgraded, MiniPCI 56K+10/100
15" Super XGA+, 512MB Ram Upgraded.
16MB DDR 4X AGP Nvidia GeForce 2 ,44.83 Video Driver, A15 Bios,
Fixed DVD- ROM Drive Toshiba SD-C2502
Removable Bay 16X CDRW Mod Drive
Teac CD-W216E, 3.5 Floppy Disk Drive.
Texas Instruments IEEE 1394 Firewire.