These changes are made specific to the user in the registry. The DWORD values in hex are located as follows:
Autosave Time (default 3 minutes):
[HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Common\MailSettings]
"AutosaveTime"=dword:0000000e
Autosave Location (default Drafts):
[HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\Options\General]
"SAVE_LOC"=dword:00000010
For the SAVE_LOC for drafts, there are four options with their decimal DWORD values:
16 Drafts
4 Outbox
5 Sent Items
6 Inbox
While the defaults should be suitable for more, there is some control for others who may work with Outlook 2007 a little differently.