My first real experience of Linux was seeing other people installing Linux on a machine in the computer lab at school. (probably around Windows 3.x time frame and I think possibly some version of RedHat). I didn't actually get to use it though (I did spend a lot of time in those labs and got busted trying to pirate Visual Basic off the Windows machines :)
I also had experience with it at University with various courses that involved Linux in some way.
As for personal use, my first use of Linux was installing some version of Mandriva (exactly what hardware I ran it on I don't have a clue). After that I installed Gentoo on an old Pentium 4 box that a family member no longer needed (ironically it was a computer that used to be mine before I sold it to said family member as an upgrade to whatever they had at the time).
I used that Gentoo box for some brief development work for a Motorola Z6 linux phone (including kernel compilation). At some point something went bad in the system and I didn't do anything with it for a while.
Then after I took it to a repair shop who cleaned out all the dust and gunk, redid the thermal goop on the CPU and replaced the busted video card with a working card my system started working again and I used that system to do a lot of software work for my Nokia N900 linux phone (software work that has made a number of other N900 enthusiasts very happy).
That system lasted all the way until just before xmas 2013 when I moved to the other side of Australia and decided the old clunker of a PC wasn't worth moving (especially since I only had a really old really heavy CRT monitor that I was using with it).
Since then my use of Linux has been confined to my Nokia N900, a VMWare VM I set up for N900 development (which I haven't used since I bought an SSD and re-installed Windows) and various interactions of various sorts with computers I dont own out there in the cloud :)
Would love to get back into Gentoo again though but I dont have any hardware I can run it on (maybe if I ever get enough money I can upgrade this Core 2 Duo to a nice Core i7 or something and use the Core 2 Duo as a Gentoo box :)