I've been experiencing some slow/denied access internet speeds recently, I've tried to load a page, it's been taking ages, then as soon as I goto ZA's firewall settings and disable the firewall, the site loads, within a second.
Are there any settings I can change to alter this, and are there any other good software firewalls out there (free) that people can recommend?
Zonealarm is one of the well recommended free firewalls, which provides ingoing and outgoing protection. If you are using XP, you could use the firewall from that, but that is ingoing only, and not as well recommended.
Have you run any anti-spyware etc, to see if that is the problem with slowness.