There was already SEO stuff going on back then people were less aware of it. I can remember during height of the Iraq war people manipulated google to display George Bush as the top result for "Miserable Failure" and there were other exercises like that happening.
It's hard for me to pick a sweet spot for the internet in many ways I feel like I've grown up with it.
I can remember the web of circa 1995 to 1997 with Gif's that wouldn't render properly in internet explorer, HTML marquee scrolling text and the dreaded blink tag being used everywhere. You needed to play search engine bingo with Altavista, Metacrawler, Yahoo, Infoseek, Lycos etc etc. And it was a crap shoot if search engines would give you useful results.
I can remember the web of 1998 to 2000 where every web developer seemed to discover html frames at the same time. We had good search with Google but pop up ads were so rife that the internet was borderline unusable. I can remember all the free webmail sites like hotmail, yahoo etc. ICQ chat was massive (whatever happened to that - it was a staple of my teen internet).
In Early 2000's Firefox came along and saved the internet by virtue of its built in popup blocking. But there was a mishmap of "Applets" and "Plugins" everywhere Flash Player, Java Applets, Real Player etc. Video (and audio) on the web was terrible half the time it would complain about missing codecs, it would buffer forever and if something did load it would be the size of a postage stamp and look pixelated as all hell. I remember Gmail came out and everyone went gaga over it's interface.
Last period that real stands out is the mid to late 00's with development of big Social Media sites, Facebook, Twitter, Youtube etc. The web got more and more javascript heavy. Web video streaming finally became useable. Google Chrome came out and flash player finally died despite Microsoft trying to revive it with Silverlight.
I kind of feel like this last 10 years are a continuation with increased surveillance and tracking.