As I note in my Profile, I originally joined the Forum in 2001 and was around for 4-5 years but eventually went on "a sabbatical" for a few years. I've been back full-time with no interruption since 2011.
I still recall well the early days and two categories of posts really stick in my mind. The first was what I would call the "TMCC versus DCS wars" as DCS was in testing then and would be released soon. The animus was real and got quite heated. The second topic was the York Meet. That, as we know, is still discussed in detail today.
Final verdict: The OGR Forum is THE place to be online for all things trains!