Here are the details of using NHibernate with MS Access. I personally haven't done this, as MS Access doesn't include main full database options like stored procedures, etc, so I typically avoid it.
I have used NHibernate with Access. Based on my experience,
If you need a file-based in-process mini-database, there are a number of options available, including SQL Server CE (Microsoft, proprietary), Firebird (free-open-source), SQLite (free-open-source). NHibernate supports all these database engines (although I have not had a chance to use them).
It can be used with MS Access. The experience is like any other experience using MS Access as a database for your application, you wish you used something else.