forgot who, could be Lebans, has a sectiuon on this sort of thign. do a google for MS Access audit log.
the main issue you have is that its not automated (ie Access / JET doesn't support the idea of triggers which woudl cause the db to do soemthign on each and every change. instead it can be done programatically. that means you adding the code to each and very form.
it also means you cannot use the data sheet view (but then persoanlly I never ever allow users to see a table in datasheet view)
because its done via code, then there is an exposure that a deliberately malicious user could circumvent any code by updating the tables from another application.
I wouldn't want to rely on Access / JET logging of activity. if you change the back end to something which supports triggers and you properly design the security procdures and policies then you could rely on the application in a legal context
I'd rather be riding on the Tiger 800 or the Norton