Deleted windowserver on activity monitor and it messed up my computer.

I accidently deleted windowserver thinking it was a bad thing before I did my research because it was taking up CPU space. And my screen went black and I could only see my mouse. So I touched my power button to see if it brought up the logout and restart menu and it did. So I hit restart. When it restarted all I could see were my mouse,backround, and desktop icons but I couldn't drag anything,and there was no dock, then the desktop icons went away and the backround started changing. From black screen to a different backround. (I have my desktop backrounds to change every 5 min.) and it kept doing that and I got scared so I just held down the power button until it shutdown. Then turned it back on. And now the only thing on my monitor is my mouse and a blurred picture of my desktop, no icons, no doc. nothing. Any advice?