Remakes- Good, but not really original.
I will tell you the top 10 best , top 10 worst,and what should be remade.

Top 10 best

10- Scooby Doo and Scrappy Doo

It's not so great. Come on! This show stunk! I mistook it for the orignal?!
9-Pokemon Chronicals

It sucks, but it's a little better than #10!They should really call it People who were booted from Pokemon!
8-Tranformers Cybertron

It is a little better than the orginal, but they should've stuck with the original plot.
7- George of the Jungle

Now this is a excellent remake of George of the Jungle because it has a fresh sense of humor
6-Astro Boy (1980's)

It's way better than the original, but it could've made some fresh new episodes like if it ran in 1987 they could ask Capcom if MegaMan could appear, but since that didn't happen, go see my version of that idea of it with those 2 intros at youtube.com/conicteamtv.
5-Astro Boy (2003)

It's the best Astro Boy remake! It moves away from the happy-go-lucky side of the show with a more darker side.
4-What's new Scooby Doo?

It is as good as the original, and it has some fresh episodes!
3- Shaggy and Scooby Doo Get a Clue!

It's even better than the original!
2- Gadget and the Gadgettinis

It has totally new plot, new characters, and new style!
1- Sabrina the teenage witch animated series

Now this is an excelent remake with an original feel.
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I think the only 2 things that should be remade that haven't already are the The Beatles cartoon and Pokemon Yellow.