My first one was something along these lines:
Pentium 75MHZ or so
windows 95
3GB hard drive
I forget how much RAM it had but I think it might have been like 16MB or so, not sure.
It also had one of those turbo buttons on it, not sure what it did but when I pressed it, it seemed like nothing happened.
This was a custom built computer, I didn't really build anything because I was like 6 or 7 at the time but I did help my dad put a few things in. I thought I was so cool having a computer of my own and thought that was a fast PC, amazing how fast technology changes.