The Nintendo Comics System was a Nintendo authorized series of comic books that featured several popular video game characters of that time. Most people who have heard of Valiant's Nintendo comic books found out about them through the comic `Nintendo Comics System', which reprinted stories from earlier issues.
Among the first few publications were trade paperback format and hardcover format collections, each containing a varied selection of stories.
Other non Valiant Nintendo related comics include those published by Nintendo Power: Super Metroid, The Legend of Zelda, many featuring Mario, Wario, and Yoshi, and the Howard and Nester series in which they visited many games. DC published a Bayou Billy series, and a Double Dragon series also exists. Not even mentioned here are the countless Japanese comics which where created for almost every game released over there, only few of which have ever been published elsewhere.
If you have any information on other titles, or foreign printings of these comics please let me know.