Hi, My Acer aspire one

Question

Hi,
My Acer aspire one is booting up and displaying my wallpaper, but no
start menu or icons. the only thing that does anything is hitting
ctrl+alt+del but it just says the task manager has been turned off by
administrator. but as far as i know i am the administrator, or i was
when i first set up my computer. there are no other users.
I