Track 1: Darkness of Fear
I don't recognize this song, so it is reasonable to assume it's a new composition, but there are a few Castlevania games I have not yet played. Although it has no nostalgic value, it is quite impressive.
Tracks 2, 3: Title Screen, Character Select
I typically avoid title themes and character select themes and my typical behavior is warranted, since they are not that interesting here as well.
Track 4: Vampire Killer [Castlevania]
It stays true to the original and diverges a bit, into a Soul Caliburish reminiscence. This interpretation kicks ass all the way through.
Track 5: Bloody Tears [Simon's Quest]
There is more diverging here, and it shares music from Lord of Vermilion (by Nobuo Uematsu). Well, I have been extensively listening to LoV, so the similarity is salient to me, but it may not be to you.
Track 6: Beginning [Castlevania III]
I do not find this interpretation very impressive. The additional compositional material does not seem to fit.
Track 7: Mad Forest [Castlevania III]
Yay! This reminds me of Goat's arrangement, which is a good thing. I have no complaints here. By the way, this is far superior to the arrangement on Perfect Selection Dracula.
Track 8: Clocktower [Caslevania III]
Yuck! I really don't like this interpretation. It reminds me of a festive amusement park and not a dark castle. The Soul Caliburish twist does not work here.
Track 9: The Tower of Dolls [X68000]
I've always liked this song and the interpretation here is impressive.
Track 10: The Wolf Revealed [Castlevania 64]
I can recognize the main theme from CV64 and another theme, so this is a medley. (This is an interpretation of the song that played after the Underground Tunnel, in the main castle. I don't recall where the other theme was used.) This interpretation is so different from the original that it might as well be a new song. It's not bad, though.
Track 11: Dracula's Castle [Symphony of the Night]
This remains very true to the original, more so than the others. In fact, I enjoy this more than the original.
Track 12: Slash [Dracula X]
Or is this Op. 13? Well, it is on Dracula Battle. I'm not sure which is the true Slash or Op. 13 anymore, after struggling with the tracklist for the Dracula X PSP OST, which contradicts the PC Engine tracklist. They're both one and the same, much like a photon is its own antiparticle! Anyway, this song (whatever it is) is pretty close to the original (whatever that is). In fact, it offers some competition for the Dracula Battle version.
Track 13: Iron Blue Intention [Bloodlines]
I prefer the interpretation used in Portrait of Ruin and the one from Dracula Battle II. In fact, I like the Mega Drive original more than this. Stay away Soul Calibur!
Track 14: Evil's Symphonic Poem (Death's Theme)
I don't recognize this song, but that doesn't mean it's not an interpretation (or arrangement).
Track 15: Dance of Illusions [Dracula X]
I can say with certainty that this is pitiful when compared to the Dracula Battle II version.
Track 16: An Empty Tome [Order of Ecclesia]
This is called 'Dusk's Holy Mark' in Order of Ecclesia. This is truly impressive, in my opinion, but only because I've become so familiar with that soundtrack. I can understand why they chose this song.
Track 17: Darkness of Fear (Arrange Version)
An arrangement of the first track.
Track 18, 19, 20: Castle, Gallery, Accessories
I don't recognize these songs.
Track 21: Elemental Tactician [Lament of Innocence]
I neither like the original nor this interpretation.
Track 22, 23, 24: Win, Lose, Game Over
If you have a problem with your hippocampal horns, then don't worry! These are so short that you won't have a chance to internalize them!
Track 25: Crucial Moment
More Soul Caliburish madness.
Track 26: Credits
Much better than "I Am the Wind".