If you had rather start over, here is a quote from Tex on the subject of "resetting" things back to the defaults.
BTW I think the thing you are referring to as the "taskbar" is called the "Panel".
"Quick way to restore the panel to default settings.
Open a konsole terminal
su to root
type cp /etc/skel/.kde4/share/config/plasma* /home/yourname/.kde4/share/config
type chown yourname:yourname /home/yourname/.kde4/share/config/*
logout and back in again
I don't know if this will fix you're desktop icons but that is a different topic.
Hope this helps. I fully understand what Tex is saying here so if you have questions about the proceedure, I will be happy to try and clear things up.