As deafult the Run button is diabled in Windows Vista's setup!
To enable follow the next steps:
1>Right-Click The Windows Vista Start Button
2>Select Properties
3>Go to the Start-Menu tab
4>Choose the Adjust button(Configure)
5>Browse the list until you see "Run-command"
6>Select it, & Press OK, (multiple times)
7>Now you should see on the Start-menu, A Run button!