Also, obviously try some PDQ Bach.    Especially PDQ Bach On The Air--above all "New Horizons in Music Appreciation"---first movement of Beethoven's 5th broadcast as a baseball game.

Priceless and immortal.

Maybe also the 1712 Overture--with Pop Goes the Weasel mixed in with Beethoven, Tchaikovsky, Brahms etc.

Also I think he has one called the Unbegun Symphony.

In his hands classical music is anything but stodgy.

Admittedly I'm not an unbiased observer, having had the chance to play second kazoo under him.