Your best bet is to take the
Metro Rail Red line (subway) from the Hollywood and Highland station to Union Station downtown. Then take either Amtrak or the
Metrolink Orange County line to go from there to the Anaheim Amtrak station, which is at the Angel stadium in Anaheim. From there you can take ART or a taxi to get to Disneyland; it's only a mile or two.
You can use the
Metro Rail trip planner to get schedules and fares:
http://socaltransport.org/tm_pub_start.php
The main
Metro Rail web site has maps and lots of information:
http://www.metro.net/
HTH,
Bob