Hunter X Hunter 2011 - 145 episodes,ongoing but will probably go on Haitus for awhile since its catching up to the manga - No filler,100 percent canon.2 movies,the first one is canon and the second probably is aswell.
Jojo's Bizarre Adventure - 26 eps,complete (this is only the first two parts of the story,the anime changes title with the third part),No filler,100 percent canon.
Jojo's Bizarre Adventure Stardust Crusaders - 23 eps,ongoing,no filler,100 percent canon and will most likely stay that way considering theres 113 manga volumes far and is still ongoing.So far theres 7 or 8 parts so the animes title may change for the next parts.
Death Note -37 eps,alittle filler,complete - i prefer the manga.
Code Geass - 50 eps,complete
Casshern Sins - 24 eps,complete.
One Piece - 660 eps,ongoing obvoiusly
Full Metal Alchemist Brotherhood - 64 eps,complete,only filler is the first ep,other than that its completely canon,although the 2nd ep shows their past whereas the manga shows in chapter 24 but i think everything else is in order.
Nisekoi - 20 eps,haitus
Hitsugi no Chaiki - 12 eps,haitus i think
No Game No Life - same as above
Akame Ga kill - 9 eps,ongoing
Kill la Kill - 24 eps,complete i think
Shingeki No Kyojin - 25 eps,haitus
Magi - 50 eps,haitus,takes breaks for 6 months after having new eps for 6 months (25 eps) and will be back in october.
I'd say go for HxH now and save the rest for later.