You can't (or at least, you can't using Access).
Access contains the entire application in a single file (the .MDB file). You
can't separate just a single form from that.
As well, there's no way to create an executable out of an Access
application. You can purchase Office XP Developer, which will give you a
royalty-free run-time version of Access that you can package along with your
application. Users who don't have Access already installed can install the
run-time version and use your Access application.
Other than that, your only option is to redo the form in some other language
that can be converted to an executable (such as VB or VC++)