Street Fighter Alpha was a guess. I mean, I'm VERY familiar with Street Fighter music, but there are a couple of themes from Street Fighter Alpha that I did not listen to. So, guessing by the very familiar style, I wrote Street Fighter Alpha there.
Tekken 3, Final Fantasy IV and Final Fantasy IX were like "SHIT, I KNOW THIS SONG, WHICH GAME WAS IT" and I started browsing through all of my PS1 games (to answer Tekken 3 and Final Fantasy IX, FFIV was more of a guess)

Also, they should have picked another song from NiGHTS Into Dreams, because with that song, everyone that played Sonic Adventure, aka everyone, will remember it from the pinball minigame, it's unfair, specially for people who actually downloaded the soundtrack because it's awesome :C (me)

Also again, I'm surprised I didn't catch Castlevania: Symphony of the Night and OutRun. Mario Kart: Double Dash, I knew it was a Mario game, but I guessed Super Mario Sunshine instead. TMNT reminded me a lot of TMNT, but idk why I didn't guess it.

ahahah rokkan had the same problem i did
on the nights part, my first guess was sonic adventure, but then I realized that the music only played on the nights table.

hey rokkan how could you posibly miss outrun i feel disapointed.

actually, no. I'm complaining because I have NiGHTS' soundtrack, and I would be really excited if it played ANY song other than this and Dreams Dreams for me to guess, by putting that song, everyone will know it's NiGHTS even though they never played or listened to its soundtrack!

also yeah metaru i'm heavily ashamed of not being able of guessing OutRun :C