Within the resort area — the zone of hotels along Harbor Boulevard and Katella Avenue — you can walk to the parks, but distances add up quickly. Disney operates a free shuttle between most resort-area hotels and the park entrance.
Beyond the resort, Anaheim is car-dependent suburban sprawl. Getting to Angel Stadium, Honda Center, or Downtown Anaheim's Packing House is easiest by rideshare or car. The Anaheim Regional Transportation Intermodal Center (ARTIC) on Douglass Road has Metrolink commuter rail connections to Los Angeles Union Station (about an hour) and Amtrak Pacific Surfliner service running up and down the coast. For day trips to Los Angeles, the train is often more practical than driving.
The Anaheim Resort Transit (ART) bus runs between hotels, the parks, the Convention Center, and ARTIC — useful if your hotel is not within walking distance of the park gates.