omg! You forgot Full Moon wo Sagashite! That series had some really nice music. I like all the songs (except the last OP):
Here's my list of favorites:
Full Moon wo Sagashite
Hikaru No Go
Avenger OP/ED (i'm one of the few that likes them)
Tenshi Na Konaimiki
Gundam Seed
Hellsing
Naruto
Princess Tutu OP
Full Metal Alchemist OP/ED
Konjiki No Gash Bell
Those series have all my favorite anime music of all time. I'm sure as I progress through more series' I'll find even more