I'm sadly another one with a huge list of unplayed and unfinished games, both for a lack of time and a lack of skill, on the bright side this gives me a lot of stuff to do on my free time.
Castlevania: unfinished
Vampire killer: haven't played it
Simon's Quest: unfinished
Haunted Castle: unfinished
The Adventure: haven't played it
Dracula's Curse: stuck at Castle's Leg
Boku Dracula-Kun: haven't played it
Belmont's Revenge: haven't played it
Super Castlevania IV: stuck somewhere after the Chandelliers Room
Kid Dracula: haven't played it
Chronicles: haven't played it
Rondo of Blood: stuck somewhere at The Dungeon
Bloodlines: stuck at Death's boss fight
Dracula X: unfinished
Castlevania SoTN: unfinished
Legends: haven't played it
Castlevania 64: unfinished
Legacy of Darkness: haven't played it
Circle of the Moon: haven't played it
Harmony of Dissonance: haven't played it
Aria of Sorrow: unfinished
Lament of Innocence: haven't played it
Dawn of Sorrow: unfinished
Curse of Darkness: haven't played it
Portrait of a Ruin: haven't played it
Order of Shadows: unfinished (probably never will)
Order of Ecclesia: unfinished
Judgement: haven't played it
Adventure ReBirth: haven't played it
Encore of the Night: haven't played it
Harmony of Despair: haven't played it
Lords of Shadow: finished story mode and DLC (missing some trials)
Mirror of Fate: stuck at Resurrection Room's Boss fight
Lords of Shadow 2: finished story mode (missing some relics, trials and DLC)
Pachinkos and Pachislots: haven't played them (probably never will)
By unfinished I mean I didn't advance too much ion the game or I can't recall how much I advanced, so I probably will start over next time I decide to play them. I'll take the chance and use this list to keep track of my progress so I'll be editing it once in a while.