need computer help quick!!

[t-maxxracer32]

hey guys i have 2 research papers due by the end of the day and for some reason i woke up and my computer had this message on the screen

windows could not start because the following file is missing or corrupt
\system32\ntoskrnl.exe.
please re-install a copy of the above file.


what the heck is wrong!?!?

i used the computer last night and left it on like i usually do..


thanks for any help!! need to get it working by the end of the day