Explorer.exe completely missing

Well, I tried updating my computer with a windows update (legal btw), and when I turned on my computer again, I had no background, no taskbar, no startmenu, absolutely nothing, I can run my programs through task manager, but explorer is 100% missing, and I think some other stuff are missing too. I even lag now at games like Trackmania...

Anyone got a solution for me?
Pretty irritating.

[SPOILER]
Also, I was stoned when I did it, so I can't remember exactly what I did
[/SPOILER]

"Can't find explorer.exe."
I've searched after it in all the files with the browse button when you start a new task with task manager, but I can't find it there either.
I used to have a backup of it too, but it got deleted as well.

EDIT:
Oh, I should also mention, can't open control.exe either...
There I get the error:

::{266EE068-A00A-44D7-9371-BEB064C98683}
Class is not registered

I have checked with msconfig too, can open it, but can't find explorer as a startup program, or tool.
And in regedit I've found it registered, but it's just missing from the library as well.

Also, I can't change my volume without manually opening sndvol, and I can't scroll with my mouse either.
But those I can live without

Unfortunately, I don't see any solution other than reinstalling Windows

Me neither, but the problem I have is that my disk is back in Norway, and I'm in the UK and won't come back for a year, and I'm poor at the moment, so I can't afford a new disk.

http://www.deletevirus.net/download/..._seven_sp1.exe

Direct download link for explorer.exe if you have Win 7 64-bit and Service Pack 1 installed.

Have you tried Windows/Flag key + R (Run) and then typing in "explorer.exe"?