need some help with Dreamcast emulator

hello folkswas reviewing the list of roms and isos available here in romulation and then I started thinking that "I never play deamcast games".So I'd like to play them but do not know what is the best emulator or how to set it (assuming you need configuration, like most emulators that i've used)so ... Would you mind helping me with that?

Chankast &
NullDC
Google them.

and ... Which of the two is better?

buy a dreamcast, they play burned games without a modchip.

doubt I can find a dreamcast, they were rarely seen in stores since the first day of they releasebut thaks for the info anyway