When I switch between windows, there is a delay of about half a second and when I want to see the windows list (is that 'walk through windows'?) that also takes some time to appear. Is this some 'smooth scrolling' effect? Some like that, but I don't, to put it mildly.
In another thread, someone suggested going to system settings > appearance > style and adjusting cpu usage. I tried different settings, but nothing helped. He also said that with oxygen one can turn off some of the fading effects, but I don't see that anywhere.

One solution I have found is choosing kde/openbox during login. Another is lxde, which also uses openbox (had to install that first). I'll play with those tomorrow.