Correct. To my knowledge, the only DSTWO specific emulators in existence are NDSSFC, CATSFC (which is better), NDSGBA, a MAME emu (don't remember the name), and DS2x86
Yes but not as easily as just swaping. You have to install fresh copy of Windows on it, and you may be able to save some stuff from old windows on it, you will have to reinstall most