You can usually start up the database while holding the Shift key. That
bypasses the autoexec and startup forms (unless someone disabled the special
keys). Then you can check for an Autoexce macro or code behind the startup
form.
If you are really worried that a database file may be destructive, put it on
a computer which is not connected to a network. That way only that computer
may need to be rebuilt if the worse happens.
Also if you happen to have Access 2007, you can open up the file and not
enable options whic will keep code from working. Make sure that the file is
NOT in the Trusted zone.