Ummm....most of the rides are the same!
That said, w/4 adults, yes you could do both parks in one day.
Here would be my plan:
Go before opening time to DL, enter and go to the L, ride Indy immediately (and Jungle Cruise if you love it like we do). After Indy, keep going to Haunted Mansion and ride it, Splash Mountain....exit and turn to your R...follow the "river" around thru Fantasyland (skip it w/4 adults)..do Matterhorn... and go back toward Roger Rabbit in toontown. Then go watch SnowWhite in the open theater (should be time for the first show)....ride the train from there to the entrance and leave for DCA.
Enter DCA and go to the R...get a fastpass for Soarin' and turn around. Go back thru entrance area to backlot area and see the animation building (significantly different than MGM, IMHO). Go back to ride Soarin', then go get FP for Ca Screamin' (back of park)...ride the little stuff on the boardwalk while you wait for FP time. After screamin', go back to backlot area and get FL for Hollywood Tower. Go see Aladdin, then FP the tower. Should then be time for ELP (stay near park entrance to watch)...hurry to main plaza and watch fireworks from DL.