I used to work for NTL technical support years ago when there were only dial-up connections. Although some of our evenings were spent tech'ing software and hardware problems - most of the time we spent finding that the person on the end of the phone had something simple wrong that they had just overlooked.
I am not saying I have never done it myself though, sometimes its easy to overlook the simple problems.
Its all true whats on these tech sites, I had calls from people trying to use computers without plugs, connect without plugging in the telephone, using the mouse as a foot pedal, blaming their fridge not working on me (only to find they have unplugged it to plug a modem in).
I currently run a website showing discounts for stores online and I get emails everyday from people thinking its my fault that their currys TV is late, complaining that they are getting spam from a website I dont even own, asking what room they have in the hotel they have booked and all other crazy questions.
The most common problems are password problems. You ask people to retype their passwords and delete the current one from their 'save passwords' - they always say they do - but most dont as they are 'sure' they are right one and just say 'I have done that' when they have not.
These days there is not much to tech when it comes to a broadband internet connection - apart from the router. Dial-up is a nightmare.
I imagine that computers and the internet for the unfamiliar is a nightmare though, I've held a few hands of newbies and listening to them really helps you set your website out correctly. Its often the case that if your too familiar with computers you miss the basics.
Ta
Baz