We're using ArcGIS 9.3 but for reasons beyond the scope of this question we have to stick with personal geodatabases (MS Access .mdb's) and multiple users. How can we set this up so only a limited few have write access and still allow the bulk of the users to use it?
You are in for a world of hurt (but I know that part of the answer doesn't help). If you don't mind the reduced speed - put it on a network share where only a few users have write permissions to the file and the others only have read.
From ESRI-L (in the comment below)
Give all users full file permissions to the folder (allowing them to create, read and modify the .LDB locking files), but set permissions for the Access database file itself to allow only the GIS Editors group to modify it.
I don't have a lot of faith in my answer but it is worth a shot :)
Access based personal geodatabases are limited to a single editor at a time, however other users will still be able to view the data while it is being edited. And anyone who has the correct permissions (Read/write/change I think) will be able to edit. This is the same for file based geodatabases. in the Esri realm Personal SDE is the lowest level of personal geodatabase that supports true multi-user editing (although very limited). Personal SDE is included with Dekstop Info and Editor(not positive) and uses MS SQL Server Express as its storage engine.