Thanks guys

I've been wanting to make that video for a while, finally got around to doing it last night.
As for frame-rates, no idea about Wolfie or DOOM but I think the classic DOOM engine is capped at 15 FPS anyway. Both these earlier games are very smooth with no slow-down on my system, Quake 1 is also running very well now (15 FPS) with the latest release (I run it at 320x240), again without any noticeable slow-down.
The version of Quake 2 in the video is v1.10 which hasn't been released yet. The frame rate for Quake 2 is mixed, it does about 12 FPS when there's not much happening but slows down in the wide open areas when there's lots of 3D geometry to render.