As Mastertech says, these ease of use apps, which I introduced as an option, are nice but use them with caution. You may like to manually disable services and see if their systems/apps on them are still doing their jobs.
Personally, I manually disable services and I haven't disabled the services on Mastertech's list except "Security Center," of which I think I know what I am doing. An odd thing, tough. Kerio 2.1.5 recognized no TCP connection work while "Windows Firewall/Internet Connection Sharing" was disabled, which wasn't the case with Kerio 4.2.x. After noticing this, I am quite happy with good old Kerio 2.1.5 with XPSP2 Firewall disabled, of course.
Talking of dependency, I think Linux GUI provides users information nicely although I don't think Windows can be replaced by Linux at least at the moment.