Heh, played a fair number tbh. First one was Three Sisters' Story, but to pick a favourite is hard. I've replayed Sengoku Rance the most, but Nocturnal Illusion, True Love and Katawa Shoujou have a special place in my heart. Fate was nice, as were Koihime Musou and Harem Party. Also Utewarerumono and Monster Girl Quest are must-plays.
Don't discount the non-H VN's either GoGo Nippon is just too cute to pass up.
Katawa Shoujo Is my favorite.... Hanako pls. is one of my waifus tough I liked all the girls in that one.
I have CLANNAD,Kanon and Fate as a must read (i didn't yet)
Tsukihime, Yume miru kusuri, and Monster Girl Quest (tough i don't really know if it's considered a VN or a game but i really enjoyed the 3 parts.) Sengoku rance to. Wanko to kurasou.... Euphoria ( unfortunately this one doesn't have a translation...)
In the NO PORN section:
Steins;Gate (I fucking loved this one.)
Umineko no naku koro ni ( simply... read it. seriously. the animu is pure shit in comparision. and WitcHunt did a great job with the translation)
Rose Guns and Days
And probably more but I don't recall them now, my problem about VN's now is that i have a lot of them in the "read" list but I don't have the time to do so...
Saya no Uta, Swang Song, all the Key ones, Fate/stay Night are just a bunch of examples...
I already playing a lot of visual novel games like clannad,little busters,shuffle, da capo,etc. but my most favorite is fate stay night especially unlimited blade works route.
For me the number one non h VN was clanad. Dem feels bro, for tomoyo not nagisa. As to overall I'm a MASSIVE fan of Type-Moon stuff with tsukihime at the top, love ciel (don't say kuroshitsuji or sith sorcery shall be unleashed).
Come see me tonight, both of them, were a riot and my sex slave is a classmate was kinda twisted. Currently waiting for some *quality time* to play school days.
I have the Black Bible: La Noche De Walpurgis, and Eroge! H mo Game mo Kaihatsu Zanmai does that Count?? haven't nearly started those two yet, still stuck at opening.
EDIT : yes & yes it is hahaha answered my own Question.. http://myanimelist.net/manga/74943/Eroge!_H_mo_Game_mo_Kaihatsu_Zanmai