First thing - your KillPrint sub doesn't make any attempt to close Word, just destroy the link to it. Try this instead:
VB Code:
  1. Sub KillPrint() 

  2.  
  3. On Error Resume Next    

  4. wrd.DisplayAlerts = 0 'do not show Word messages (such as "printing hasn't finished yet")

  5. wrd.Quit False        'Quit word (without saving changes to documents)

  6.  
  7. Set wrd = Nothing 

  8. MsgBox "Print Cancelled!" 

  9.  
  10. End   'There are lots of arguments for not using End - unloading forms would be better.

  11.  
  12. End Sub


And as far as enabling you cancel button goes, riteshtandon was on the right track.. DoEvents is what you need. Just put it into your code in several places, not just at the start - especially within loops and before+after lines of code that take a long time to execute.