About the troubles with playing movies:
Just to make sure you have all the codecs installed, please, run:
sudo apt install ubuntu-restricted-extras
Also, there is a known bug related to playing videos on Ubuntu 22.04 using the preinstalled default app.
Luckily, the workaround is easy. Just remove gstreamer1.0-vaapi
sudo apt remove gstreamer1.0-vaapi
Please, let me know if that helps.
Cheers!