Kof '99 Dream Match on the DC is Kof '98 The Slugfest/Dream Match never ends on MVS/AES (the one with omega rugal and no story line). It was called that because it was released early into 1999 and SNK didn't want it to seem old. KOF '99 Evolution on the DC is KOF '99 The Millenium Battle on the MVS/AES (the one with K, Krizalid and Nests).
Thanks for asking anyway.