Best Practices For Graphics

What are the best methods for designing graphics for HD broadcast?
I have designs that look great in Paintshop Pro but when they get to the stream they are aliased terribly.

Then I have other logos and such that look great on the stream (not by me).....

I cannot for the life of me figure out how to make them look smoother.....

I use transparent png for my graphics but they just loose something in the translation.

Any suggestions or help would be greatly appreciated!

David