Here is a link to a copy of the Webster-Dictionary (234936 words) from 1997.
http://packetstormsecurity.org/files/31994/websters-dictionary.gz
Also, you can take a look at the following search query, many lists are available. Scroll to the lower portion of the first page to begin viewing the available word lists. All of these lists are plain-text.
http://packetstormsecurity.org/search/files/page1/?q=word%20list
Regarding the mdb file that you had mentioned, Microsoft Access would allow you to export the dictionary file into other forms such as csv and what not. A free software alternative for exporting said data that you may also be interested in viewing would be the "Base" application included in the LibreOffice suite, it may have the ability to read/export the mdb file in question.
I know this may be a long shot as I am uncertain of the structure of this database (mdb) nor the structure of an mdb file itself; I believe it is plain text though. In theory, if the database contained only one table (for simplicities sake), you may be able to write a small script to parse the mdb file in question, in turn, pulling out the desired text.