Those are good choices above. If you want some alternatives:
For St. Matthew: Leipzig Radio Choir, Staatskapelle Dresden, directed by Peter Scheier.
Philips 412 527-2
For B Minor Mass: Also a Leipzig, Scheier, etal
Philips 432 972-2
And...Academy St. Martin, Neville Marriner
Philips 432-972-2
Then you can move on to the St. John Passion and the Christmas Oratorio
For St. Matthew: Leipzig Radio Choir, Staatskapelle Dresden, directed by Peter Scheier.
Philips 412 527-2
For B Minor Mass: Also a Leipzig, Scheier, etal
Philips 432 972-2
And...Academy St. Martin, Neville Marriner
Philips 432-972-2
Then you can move on to the St. John Passion and the Christmas Oratorio