Welcome back. I was running RRT2 on xp pro. Needed a run in compatability mode file as I remember. I also have Sid Meier's Railroads, and RRT3 which I don't like as well.
I tried installing RRT2 on XP Pro. "RRT2 does not support Windows NT". Couldn't even get past that. And TTD didn't even attempt to (Install immediately did a GPF).
I'm a bit intrigued by the other sims here (Giant Industry, Traffic and Transport)