I am a little new to the anime, but here is my top ten at the moment!
1. Shuffle! This is the only anime i have ever watched where I almost crying and laughing at the same time! I didn't think I would like harems, but once you look back at all the anime I watched most of them were. This will probably remain my favorite for awhile.
2. Seto No Hanoyome. I love this anime so much, it's crazy characters and art make it my top. San is my favorite character of all time! CHIVALRY!!
3. D.N.Angel. I heard the Manga was way better and I am going to read it sometime so maybe my opinion will change after that, but still this anime is amazing.
4. Chobits. My friend Amy told me about this anime, and it was the first anime I EVER watched! So lots of sentimental value
5. Kaze No Stigma. I still haven't finished this series, but what I have watched was great.
6. Fruits Basket. I actually didn't really want to watch this show because it always seemed so popular and I was trying to find some that not many have watched, but I got over it and watched it and I'm glad I did.
7. Law of Ueki. Ueki is my 2nd favorite anime character ever!!!
8. Zero no Tsukaima. This used to be my favorite anime, but I watched it way too many times so it did get a little old, but still is a pretty awesome anime.
9. Nagasarette Airantou. Ikuto is like the luckiest man alive...
10. Otome wa Boku ni Koishiteru. I tried this weird anime, i probably won't ever watch a cross dressing anime again, a friend recommended and I had no clue what it was about
THOSE ARE MY TOP TEN!