Hello alicez. To answer your question, Spybot-SD can co-exist with these programs because generally they're all anti-malware scanners, except AVG AV. I believe Spybot-SD can co-exist with Norton IS 2005. I would say it is a positive benefit... I mean having Spybot-SD on your computer because it a malware scanner. TeaTimer is the Resident Shield of Spybot-SD. It alerts for changes in the registry, homepage, etc. Just like Winpatrol... much like a Watchdog.
Also, once your NIS 2005 subscription runs out, I would suggest download a "free" AV such as Avast!, AVG 8.0 Free, or Antivir. A firewall would be preferable such as Comodo or ZoneAlarm Free.