Screen wave in Desktop while powering up, then in Chrome & iTunes (started with Finder not responding?) and flickering in Contacts I am on OS X El Capitan v 10.11.1, MacBook (13-in, Mid 2010)

I am not a power user so if I should ask this in another community would someone please let me know?

Current issue: kind of like "the wave" fans do in a football stadium, my screen has a wave rolling up the screen in Chrome (where tabs also flicker) and iTunes now. And not sure it's normal but sections of Contacts are flickering.

Possibly related question:  if I have to uninstall something potentially incompatible with El Capitan, how do I identify what that is?

History: Thank you for the answer from Steve Chambers under "My Finder is not responding and there are no documents on Desktop after downloading OS X Yosemite". I had that same issue. I clicked to Relaunch Finder after pulling up the dialog via holding command + option. Then I powered off and rebooted in Safe Mode. 

The end of the answer to the above issue included the suggestion there might be something incompatible with Yosemite that would need to be uninstalled--is this the same for El Capitan, and if so how does one know what to uninstall?

Not sure how to describe it but while the desktop started to come back on, horizontal rows started to roll or scroll from bottom to top of the screen. Like a wave in a football stadium, only rolling south to north. This only happened while powering up.

The good news is my desktop files are back and Finder is available to me. And Safari works fine.

Screen wave happened in Chrome as well. I uninstalled and downloaded Chrome again but it didn't help. The top tabs are shuddering and the pixels in the right scroll bar and any website page are rolling up a bit similarly to how my desktop screen acted upon powering up. But I'm okay using Safari.
Are you sure this isn't a display issue? Plug in an external monitor. If you don't see the same "wave" and flickering on the external monitor, your built-in display may be flaking out. If you DO see the same weird display errors on the external monitor, then something else is wrong (perhaps an incompatibility, but something that is causing that much of a display mess is unlikely - possibly your video card is having issues).

If it is the internal display, sometimes very gently flexing the lid of your computer can temporarily fix this. Contact points between the display cable and the screen can become loose or break, causing weird display bugs like flickering or rolling lines. Wiggling the screen can put things back into contact - but this is not a permanent fix, you will eventually need to use an external display all the time or replace the laptop screen. (My old 2007 MBP started doing this a while ago - I was able to "wiggle" it into working again but do not trust that it will keep working much longer.)