SFC in Vista;
System File Checker (SFC)
The System File Checker is an important application which scans the integrity of all the protected system files on your PC. Should it locate an incorrect version of a specific protected file SFC automatically replaces it with the correct Microsoft version.
To check your Windows protected files, proceed as follows:
1/ Click the Start button
2/ From the Start Menu, Click All programs followed by Accessories
3/ In the Accessories menu, Right Click on the Command Prompt option
4/ From the drop down menu that appears, Click on the 'Run as administrator' option
5/ If you have the User Account Control (UAC) enabled you will be asked for authorisation prior to the command prompt opening. You may simply need to press the Continue button if you are the administrator or insert the administrator password etc.
6/ In the Command Prompt window, type: sfc /scannow and then press Enter
7/ A message will appear stating that 'the system scan will begin'
8/ Be patient because the scan may take some time
9/ If any files require replacing SFC will replace them. You may be asked to insert your Vista DVD for this process to continue
10/ If everything is okay you should, after the scan, see the following message "Windows resource protection did not find any integrity violations"
11/ After the scan has completed, Close the command prompt window
Though i think you will be better running Vista's startup repair first;click here
Try removing the keyboard and re-connect also.