In order of merit:
1.Don't Torture a Duckling (1972) ***
2.A Lizard in a Woman's Skin (1971) ***
3.Perversion Story aka One on Top of the Other (1969) ***
4.Beatrice Cenci aka The Conspiracy Of Torture (1969) ***
5.Massacre Time (1966) ***
6.Seven Notes in Black (1977) **1/2
7.The Senator Likes Women (1972) **1/2
8.The New York Ripper (1982) **
9.Zombi (1979) **
10.Four of the Apocalypse (1975) **
11.White Fang (1973) **
12.A Bullet For Sandoval (co-director) (1969)
13.The House by the Cemetery (1981) **
14.The Beyond (1981) **
15.The Thieves (1959) **
16.City of the Living Dead (1980) *1/2
17.Aenigma (1987) BOMB
I had the good fortune of watching 3 of these - nos. 1, 4 and 9 - at last year's Venice Film Festival, with Fulci fans Quentin Tarantino and Joe Dante, not to mention Fulci collaborators Barbara Bouchet and screenwriter Dardano Sacchetti, in attendance

!
Apart from WHITE FANG, which I haven't watched in over 20 years (so take that rating/ranking for what it is

!), I've caught up with all the rest in the last couple of years. I have only been an avid fan of Euro-Cult cinema for the last 5 years or so (ever since I got myself an internet connection) and, before that, only the best-known works of Dario Argento, Mario Bava and Sergio Leone held any interest for me at all.
Now that I've ventured into several facets of Fulci's work - comedy, adventure,
gialli, horror - I can safely say that I much prefer his
gialli over all the rest; as a matter of fact, the first 3 films in my list are certainly among the best in the entire
giallo canon.
As for his "gorefests", while they are decidedly a matter of taste, I have to say I'm finding them more acceptable the more I get under my belt...
P.S. Brook, I don't know if it's a typo on your part or not, but the correct word is
giallo (or
gialli for plural)

. By the way, A LIZARD IN A WOMAN'S SKIN is a
must for any self-respecting Euro-Cult fan!