City of Rott

City of Rott is a 2006 animated zombie film by Frank Sudol, who performed all filmmaking duties himself. The film uses 2D limited animation in a style similar to South Park. A sequel, City of Rott 2, was released in October 2014 through Amazon.com.

The film revolves around Fred, an elderly man with a walker, which he uses as a weapon. Fred appears to be losing his mind, believing his walker speaks to him as he travels through an infested city on a quest for a new pair of shoes.While searching a mall for the shoes, Fred encounters a recently bitten nurse. With no knowledge of a cure for the infection, the nurse quickly becomes a zombie, forcing Fred to flee the mall. Outside, he meets Jon, a skilled shooter who decides to help Fred escape the city. However, Fred loses his walker in an ensuing scuffle with zombies, where it gets taken from him by the nurse. Unwilling to abandon his closest friend even as his slippers assume the role of inanimate speaking object, Fred abandons Jon by stealing a motorcycle. ........

Source: Wikipedia