So much Bach, where do I start?

Yes, try the Orchestra Suites also. If not a somplete set, I think #2 is the most popular??

That one's my favorite; usually they're two to a CD. One more thing I just thought of, you might want to ease your way into Bach's keyboard music through Stokowski's orchestral transcriptions of some of those works (remember the opening Toccatta and Fugue in D Minor from the original Fantasia?). There was a very good Chandos recording of them years ago which I have on vinyl and may be available on CD, and Telarc had some of them on its The Stokowski Sound CD with Kunzel and the Cincinnati Pops; I'm sure there are other versions available, as these were quite popular. Worth looking for, as they're a lot of fun.

I listen to the Brandenberg Cd's a lot, my issue was released by a mucical society (can't recall the name) and is on loan right now. I just picked up "The Art of Fugue", Bach's last piece and it was done by Rinaldo Alessandrini and is on Opus 111. I have been tempted to pick up other performances of the Brandenberg Concertos and have a music picker that just called with a Scottish or Irish performance (can't recall which) but will pick it up next weekend. I am also pretty new to classical music, but like anything else know what I like.

Everybody who loves Bach is going to have their own favorites for recorded versions. My choice for the complete Brandenburg concertos is a relatively new recording by the Boston Baroque (Martin Pearlman, Director) on the Telarc label. It features period instruments, and the recording quality is superb. Another version which is also excellent is the recording by Tafelmusik on the Sony label. If you like violin, I recommend the solo and double violin concertos, recorded on the Harmonia Mundi label by Andre Manze, Richard Podger, and the Academy of Ancient Music. The Orchestral Suites are also well worth owning, and the version by Christopher Hogwood and the Academy of Ancient Music on the London label is excellent. The Well-Tempered Clavier, a group of some 24 preludes and fugues, is also a great work. There are two good recordings of WTC, one on harpsichord by Davitt Moroney (Harmonia Mundi) and the other on piano by Andras Schiff (London, 2 CD's). I also like the Goldberg variations, with the most famous recording by Glenn Gould. There are 2 more recent versions which also are commendable by Andras Schiff (London) and Ton Koopman (Erato). Bach was also a master of choral music, and no collection is complete without his "St. Matthew's Passion" (try the John Eliot Gardner version on Deutsche Gramophone with the Monteverdi Choir), and the "Mass in B Minor" (2 good versions: John Eliot Gardiner with Monteverdi Choir on the DG label; and the version directed by Robert King with the King's Consort on the Hyperion label.)

Yes Brandenburg Concertos are very good, too many good versions to mention, I have Pinnock/Archiv label.

What you really want though going by your description are
Vivaldi concertos, which can make Bach sound stodgy by comparison. Get the entire sets, not just "4 seasons".
Great sets include, Opus 3 L'estro Armonico, Opus 4 La
Stravaganza, Opus 8 Il Cimento (includes 4 seasons), Opus
9 La Cetra. Each opus contains 12 concertos, exciting and
passionate as baroque music gets. Many good cheap sets available by Pinnock, Hogwood, Marriner and others.