Of these five I only have the firewall enabled on my Windows 7 desktop. And that only because I can’t be bothered to look into some issues with interdependencies when you disable the Windows firewall. (Can’t recall what exactly now.)

I don’t think the firewall adds anything significant to the startup time; it is just one of the dozens of services that start automatically.

Then, for many people an antivirus program may also be useful. Would that add 5 to 10 seconds to the startup time of a modern machine?

For the other 3—anti-rootkit, anti-spyware, keyboard scrambler— why do you think they are necessary for every user of Windows?