Avast 4.8 and Firefox 3.6.8 and 64-bit windows 7. It caught 3 instances of the same malicious script attempting to load from that page.
Oh well, I'm not to worried about speeding up my browsing anyways. 3 ghz quad core 64-bit processor, 6 gb of ram, and a 15mbps connection that I built last year.... Only thing slowing me down is the internet. Besides, I read the tweaks on that page. I'm willing to bet you are just experiencing a placebo effect in most cases anyways. None of that stuff should significantly change your browsing experience unless you have a LOT of connections at once.
By the way. AVG sucks. If you want to speed up your computer, get rid of that piece of bloatware. The last couple versions have gotten as bloated and resource hungry as norton. I recommend Avast. They have a free version, just like AVG, and Avast uses significantly less resources while still offering the same or better protection.
Your tweak for windows startup does work, but, expect many of your programs to load slower. Windows indexing doesn't really mean that all those additional programs are running. Windows just prepares certain things for if you run them, so that they will load up quickly. Just telling you, since that article you are getting it from was obviously written by someone who found out about the tweak elsewhere and doesn't really understand what it is....