As others have said, there are only really 2 ways to get to the parks . . . there is an entrance into DCA right across from the main pool and there is an exit a bit off the lobby into Downtown Disney where you go to walk down to Disneyland park.
Depending on your time constraints, definitely be sure to at least hit the rides at DL park that are unique to DLR. Try and get a reservation for Blue Bayou (I prefer lunch time) . . . it's a good meal in a lovely atmosphere.
Blue Bayou Lunch Menu - Disneyland
There are lots of good tips and such for things to do, see and eat in the DL: Touring forum as well as the DL: Feasting and DL: Making More Magic forums.