1 - A whole lot. There are lots of emulators out there for the DC, someone round here had a list running of all the full/near fullspeed ones, but i dunno where it went.
2 - Most all dreamcasts play cd-rs there are a few very late model 2000 ones that will not. Odds are though if your dreamcast will read CDs at all (lots of dreamcasts have worn out over time and can no longer read CDs at all, of any sort) it will play homebrew fine. To test, just put any music CD into your dreamcast. If it can play it, then there is a 99.99% chance it will play homebrew.
For an idea of how emulation is, pretty much every system before the genesis is emulated fullspeed-near fullspeed. Genesis is being worked on at the moment and within the next few months a fullspeed emulator should be released for it. For SNES there are two excellent emulators that run near fullspeed in most games.
We also have arcade emulators to play pretty much any game before 1990 near or at fullspeed. On top of that there is a ton of homebrew and a bunch of multimedia applications (for divx, vcd, mp3, etc)
Bookmarks