Do a custom install of Office 2007. You can instruct it to leave your Access
2003 on the disk.
Access 2007 can open mdb files created in Access 2000, 2002, and 2003, and
you can modify everything (tables, forms, code, queries, ...) It does add a
few more hidden system tables (e.g. for managing the nav pane.)
As with previous versions, there can be issues with libraries and ActiveX
control versioning.
If you are running multiple issues of Access under Windows Vista, you need
to be aware of the issue described here:
Errors using multiple versions of Access under Vista
at:
http://allenbrowne.com/bug-17.html
For a list of other issues with Access 2007, see:
Converting to Access 2007
at:
http://allenbrowne.com/Access2007.html
The strangest one is that I am losing help in Access 2003, i.e. sometimes
the help screens come up completely blank (apart from the title bar.)