Brown spot on clothes

Recently I have been noticing brown ( brun marks) spots on my colthes and a burning smell. Also my son button have been getting stuck on the front rim of the dryer and I notice some small pieces of plastic in the dryer. I believe its the Felt guide assembly or the lower seal.

Any ideas

If so what part would I need ?

Thanks
LV

Thanks Matt

If possible what the best and easiest way to repair this?

Liborio