The four titles they picked for Dreamcast, and while I love Sonic Adventure and Crazy Taxi, were poor choices in my opinion. Yes, they're Sega classics, but they aren't the popular games. There were
threads on SPUF shortly after the horrifically buggy launch of the Dreamcast Pack making suggestions for a pack 2, and there were some really good titles that came up.
Sonic Adventure 2
Skies of Arcadia (as a result of these threads, I went out and bought the Gamecube remake the same day)
Jet Grind/Set Radio (US version was Grind, Pal version was Set, same game though)
Virtua Fighter
Dynamite Cop (my personal favorite)
There were also calls for some of those great third-party titles
Marvel vs Capcom
Soul Calibur
I know there was a lot more, but I can't remember a whole lot. I didn't pick up a Dreamcast when it came out, and by the time my brother bought one, it was already gone.
Oh yes, someone on that SPUF thread mentioned Typing of the Dead.
Relating to the buggy launch of the current Dreamcast titles, while efforts were made to fix the issues, a lot of them persist, enough to not buy the pack in my opinion; had I known, I wouldn't have gone there myself.
-Lack of controller support; this isn't exactly true, but controllers freak out when you try to use them, especially in Sonic Adventure
-Useless config tool; don't know if they fixed this, but the config tool didn't do anything when it was first released
-Save issues; they DID fix this, but the game's didn't properly create save directories when first launched
-Keyboard controls; without a joystick, you're forced to use WASD to play the games, and that doesn't fare well with a 3D platformer or a driving simulator. No problem with Space Channel though, but I haven't bothered playing Bass Fishing.
-Porting issues; many people speculate that these are ports of their respective Xbox360 versions, as evidenced by the fact that if you play Sonic Adventure in another language, exiting the game will ask you if "you want to return to the Xbox 360 dashboard"