I bother because it is idiocy not to.
It is automatic & pain-free & affords protections against known vulnerabilities. (The very same reasons you have upgraded from FF4.0 to FF4.0.1).
It does not impact (generally) the usage of your system (UAC I do have enabled - for whatever its worth) or (generally) system performance.
The latter cannot be said about (what I consider to be worthless [to me]) A/V type "protections". (Look at how many have A/V protections installed, yet guess what, they still get infected.) I did not buy my relatively modest computer only to have its performance dragged down [I have a Mozilla browser to do that

] by an A/V, nor do I worry about visiting "porn" or "warez" sites "because I might get infected". (Every day you hear - my A/V is up to date, I don't visit porn sites, yet I got these windows popping up & now I have a virus

.)
That is, Win2K has multiple, public, unpatched vulnerabilities which will never be fixed.
Right. And that said, if it were my OS, it still would not concern me - I would not limit it's, my, usage because of that. If I were worried about that, I would upgrade (to XP

). (Though I have/use W7 too, I find no advantage, no feature in Vista/W7 that would otherwise entice me to switch from XP.)
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