Time Killers?! BWAHAHAHA! Talk about a crap fighting system... though I will admit it's fun to play around with it in MAME (I have a cheat to use Death).

For me, its these games:

-Street Fighter III: 2nd Impact: I tried 3rd Strike, but I never liked it (in fact, Capcom never officially moved 3S out of the beta testing phase in the arcades)... something about how the game flowed felt wrong compared to New Generation and 2nd Impact. New Generation was fun, but 2nd Impact has everything the first did, plus extras. It's even better on the DC with S.Akuma and Gill both being playable.

-The King of Fighters '98 (DC version): I'm a sucker for the 'no-frills' 3-on-3 fun that is KOF '94-98, and I was torn between giving '96, '97 and '98 the top spot from this series. '98 won out because of the bigger roster, and the Orochi versions of Chris, Shermie and Yashiro. The Dreamcast port was marginally improved, with 3D backgrounds as opposed to the Neo Geo's 2D BGs.

-Super Street Fighter II Turbo: SF2 got more and more balanced with each incarnation, so logically the last would be the best. The fact that my favorite character up until Alpha 3 made his debut here helps seal the deal.

-Street Fighter Alpha 3 (home): Just like the SF2 series got better with each game, so did the Alpha series. While Vism rules the tournament scene, I find my A-Karin to be a fun choice. The home market got the better deal, since they added Guile, Dee Jay, Fei Long, and T.Hawk, as well as new versions of Ryu (Evil) and Akuma (Shin) (my guess is the first 4 weren't ready by the time the game hit the arcade, so they had to be included as home version-only characters).

-Soul Calibur (DC version): Just like other games got enhancements coming to the home, SC1 is no different. Namco put alot of effort into their DC offering, and it shows. All the character models were overhauled, the stages were made much better-looking, and the opening from the arcade was scrapped, replaced by a very nice sequence using alot of neat effects (one look at Ivy's scene, and you'll know what I mean). Of course, Namco saw fit to add 2 new characters and stages (Cervantes, Inferno, Maze of the Dead and The Adrian and the Fortress). Add this to the fact that SC was a first-generation game, and you've got an amazing game on your hands.
(side note: Would anyone happen to have a US version ISO? The version I downloaded seems to be EU with a 50/60hz switch option on boot)

-Super Smash Brothers: Why not Melee? Well, there's something about the original that just makes it better than the sequel. Granted, spike moves are abusable to no end here (no lag time, good power and no recourse), but I just can't help but feel Nintendo screwed something up in Melee...