:| should absolutely not have been big, wide-open eyes. That would be O_O. :| should be absolutely stonefaced, like an old Korean getting their photo taken. Zero facial expression, signifying "i am not amused" or somesuch.
Outside of IM, in the mid-2000s and earlier, the Internet was more of a space of personal expression and burgeoning e-commerce.
There was Geocities and Anglefire where anyone could create a personal homepage with rudimentary HTML skills. You could show off your personality and share your interests, and (some) others would be excited to find you and sign your guest book. You'd be excited every time the hit counter on your page went up.
Talking in real-time, over IRC usually, was the first taste of true globalisation for many. There were other, older forums around like BBSs, but these were even more techno-niche nerd havens. The web forum (PHPBB) later came along and created what I consider to be the protoweb of what we have today. Profiles, display pictures, post counts, threads and boards, etc.
Another large difference was that the Internet was still a very collaborative space. Services usually had open APIs, so that you could write or use software that brought the services you wanted into the format you prefer. Think: all of your IM accounts in one messaging app, all of your website news feeds delivered to an RSS reader, and data that easily flowed from one space to another. Unfortunately, it wasn't long before these same services saw the business sense in restricting users from exporting their data, thus confining them to "walled gardens" where they were readily subjected to ads, and without recourse to leave. And thus the API died.
There was essentially no presence of celebrity on the net as we know it today. Before MySpace, at least, you would be required to go out and search for Sean Connery's personal blog, or Paris Hiltons fashion tips. Today, it's difficult to avoid these things being pressed upon you. At this point in time, you chased people, now it seems the web has them chasing you.
Commerce was a commonplace part of the net as early as the 90s, depending on your idea of commonplace. Nobody trusted computers with their financial data like credit cards. Giving your address to a seller felt wildly reckless... until it didn't. A little bookstore called Amazon started the novel idea of efficient online sales with less of the burden of storage, eBay rose seemingly overnight, Elon Musk made his fortune selling PayPal, we all collected Net Beans like they'd be worth anything.
Video playback and other multimedia features bled their way into the web from the millennium onward. Online journalism felt like it was in it's fittest shape.
There was a huge culture of shareware in every market. Shareware games, file utilities, media players, everything. It was how you hoped to be discovered as a software author. We'd load diskettes with BonziBuddy and cursor themes and trade them with friends in break rooms and schoolyards. The coolest among you know how to find pirated games and bootleg software.
Comment sections were truly, deeply, disgusting hives of scum and villainy.
Maybe these are typos:
BBCs --> BBSs (Bulletin Board System)
BonzaiBuddy --> BonziBuddy (complete garbage virtual assistant)
Also, newsgroups were an early way to post and discuss with interesting people from many parts of the world. It was a mindblowing shift from the existing media landscape, which used the firehose-delivery-methods of TV, newspaper and radio.
My favorite bit of trivia on this subject is that in Perl, if you have something list-like with lots of potentially empty values where the length isn't the same as the number of things in the list, you can force list context and get a quick count by assigning to an empty list.
The end result is the unofficial "buttse" operator: =()=.
msn messenger was the closest you ever got to discord. bbm was the equivalent of the exclusive in-group you get with apple iMessage users nowadays. both were pretty fun but pretty primitive!
AOL actually made a native Linux implementation of AIM, but they stopped updating it, so it got pretty out of date. I mostly used Gaim/Pidgin to connect to AIM/Yahoo/MSN and later on Google Talk through XMPP.