Panderios come with either nylon or skin heads. Nylon is often louder and more durable and can be tuned higher. Singly ply nylon is more versatile: double ply nylon is more focused in tone and louder when tuned to higher pitches. Skin has a more mellow tone and can be tuned low to medium pitches.
Platinelas (jingles) are made of steel (very bright sounding) or brass (darker tone). Pandeiros most often have five or six sets of platinellas. Some larger drums have seven sets.
10″ is the most common and versatile size. 11″ drums can be louder.
Here is a brief comparison of most of the pandeiros available from Virada Drums:
Demo videos for each pandeiro can be found on the product page and also on YouTube