settings w.m uses long time to respond

I have a Macbook pro running 10.10.2 (Yosemite I believe..) and setting with more (the search field at google homepage) takes a long time (ca. 1 minute) to respond after clicking it. I get the loading icon on the mouse and just have to wait...

Another problem is the keys used to change volume (F10-->F12), they don´t work, neither does the button up on the right area of the screen (don't know what it is called, its grey and next to battery and wifi...

This is a big issue since I listen to a lot of music and don´t have time to enter settings each time I want to adjust the volume. I am now going to download Yosemite one more time to see i that helps (already download two times).

All help will be appreciated 🙂

- Mr.Ginger