1. She explained to me how to draw a dinosaur.

2. She explained how to draw a dinosaur to me.

(Are both okay? Which one is better?)

3. Susan suggested to us a very good idea.
4. Susan suggested a very good idea to us.
(Are both okay? Which one is better?)

1 and 4 are fine.

2 would be fine if you omit "to me."
3 would be fine if you omit "to us" or move that phrase to the end of the sentence.