Yes after you beat the Pokemon league
Pokemon Emerald takes place in a different region than Kanto (the home of Pallet Town). You cannot go there in Pokemon Emerald.
press start when in your home and press xyxyx
when you see all the Pokemon in Pokemon emerald go back home and talk to professer birch. he will let you pick 1 of 3 very rare Pokemon.
Your Home
Petalburg Gym Back near your home town
It isn't called "Eight Island" in Pokemon Emerald, like it is in Pokemon FireRed and LeafGreen. It's still called "Navel Rock" and it is still home to Lugia and Ho-oh. The only way to reach it in Emerald is to receive the Mystic Ticket. Sorry, I don't know how to get the Mystic Ticket, but I think you need to go to a Nintendo Event to get it.
In Mossdeep City which incidentally is also home to the Twin Gym Leaders (Psychic Type)
you see her in your home town and after completing the Pokemon league, you also see her in rustboard city and near a Pokemon ranger... thts all the places i can think of chow :)
You can, you have to go to Fuschia city where the safari zone was in leaf green and fire red. After that save it and turn it off to get to the home screen then click migrate from emerald UPDATED BY HEARTLESS: Make sure you don't forget to capture the Pokemon in Pal Park! I've made that mistake before, when I had no clue what I was doing, and I thought my Pokemon were lost!
u hawe to win the battle dome 10 times and do to your Pokemon kyogre if you don't have kyogre you can go to the to your home and talk to your Pokemon swampert THAT MAKES NO SENCE
horses come home
may/brendan will get tired of catching Pokemon and just stay home and play Pokemon emerald in their game boy. their gonna be lazy and become a couch potato. :-D