This may have worked the first time, but smss.exe is a legitimate system file, as long as it's located in the system32 folder
It's been a few days, but if you are still there, do this:
First, restart your computer tapping F8 repeatedly until the Advanced Options menu appears.
Try "Last Known Good Configuration".
As this may not work, try this.
(You will have to do this on another computer)
You will need a blank CD-r, from any local department store. Maybe you have one already.
Download Windows Recovery Console here
Download, and install Imgburn from my sig.
Install Imgburn onto your computer. You can choose No when it asks to check for a new version, the older one will work fine.
Using Imgburn, Choose "Write Image file to disk". Choose the folder Icon with a magnifying glass to choose your windows recovery console ISO. When ready, burn the ISO to the disk, choosing the large "Iso file to cd" button on the bottom.
When complete, close Imgburn and all other applications.
Restart your computer(with problems). Open the CD-Rom Drive and insert your newly burned disk. Restart the computer again.
Boot to the CD...let it finish loading.
To boot the Cd:
When you start windows, choose Boot Device Menu - the Hotkey is probably F12 or C. Try pressing F12 repeatedly, until the boot menu appears.
Choose your CD-Rom Drive.
When the "Welcome to Setup" screen appears, press R to start the Recovery Console.
Hope this helps.