They've done the first ep. of each season "commercial-free", though they did a long commercial spot before and after the show. It was very easy to get hooked on 24 in season 1 with a very movie-like first episode without all of the commercials.
24 is great on DVD. (As is Babylon 5, Firefly, Farscape, ...)
I'm looking forward to Season Three - haven't seen a minute of it when it airs. It should be on DVD probably come September.
Season Three of CSI will be out, too, but I've seen every ep on tape delay, so I don't know if I'll rent that one. The problem is that there are very few TV shows on DVD that I have much interest in. It might be fun to see a bunch of LA Law, but it's not available. CSI is great, but CSI: Miami leaves me cold, thanks to my distaste for David Caruso.
Speaking of DVD's, my Netflix Queue is empty so I gotta go pick some more things to watch...
Michael