I worked at a local mom and pop ISP at around the same time, probably a few years later. Those sorts of customer calls were the best (after they were resolved of course.)
* One guy would call at 2 or 3 AM and scream into our voicemail "Internet's DOWN! FIX IT NOW!!!!!". His wife would call the next day and apologize.
* One time, someone called irate that their dialup service wasn't working. He called the number we gave him, and all he heard "was a bunch of ringing and static". After several minutes we figured out he was dialing the modem bank from a telephone and expecting to use the Internet without a computer. He did not own a computer, and was quite upset we had not told him he needed one...
* It took two or three hours one time to figure out why someone couldn't connect. Helpfully, they figured it out themselves -- they were entering "the letter zero, not the number zero".
* A guy called up one time wanting to tell us about an interstellar propulsion device he developed (which also, of course, could cure cancer if the 'magnetic field' was reversed.) I suggested he call the Jet Propulsion Labs and gave him the number.
For me, the support calls were always the worst and I was very glad when the company got big enough that I no longer had to regularly take calls (although the ones I did get were the worst of the worst.)