Unfortunately not; Legendaries can't breed at all, not even with Ditto.
No, you cannot breed Legendaries with the exception of Manaphy.
You collect all 8 Kanto badges.
There is not a daycare in kanto
The game is set in the Kanto region automatically.
what do you mean by old
blue is the last gym leader in kanto after you beat the elite 4 you can go to kanto by taking the ss aqua in olivine city and go to kanto, battle the gym leaders, and capture legendaries
A wide variety of different Pokemon that cover each others' weaknesses.
Beating the gym leaders, dojos and elite fours unlock certain legendaries. You get kanto legendaries if you beat ALL kanto gym leaders and elites. And so forth. For certain legendaries, check out the pokedex for how to obtain them. Beat ALL of the people, and have full access to all legendaries. Go on any map and keep walking around slower than usual (i always miss them) until one pops out. if it takes too long, go to another place. They aren't hard to get, really. REMEMBER, YOU CANNOT CATCH THE SAME LEGENDARY MORE THAN ONCE. But, you can catch a normal kyogre and a mettalic one, for instance. JUST NOT TWO OF THE SAME COLOR.
I'm pretty sure you face the champion, win, go to Kanto, beat the others, beat red, get legendaries, and then your done.
No, you cannot go to Hoenn in Pokemon SoulSilver, but you can still get the Hoenn legendaries. Pokemon SoulSilver is a copy of Pokemon Silver, and you can only go to Johto and Kanto.
The legendaries can be found in these locations: Mt Ember, Power Plant, Seafoam Islands, Cerulean Cave. The legendary dogs have no specific location since they roam around Kanto.
You can't get to Hoenn from Johto as far as I've been in the game but there are the two legendaries from Hoenn that appear in the Kanto Region, Latios and Latias after you defeat pretty much everything you can find them in any of the routes
These are the legendaries in diamond that you can get without any cheats:DialgaUxieMespriteAzelfHeatranRegigigasGiratinaCresseliaRotom
use hacks:P:P:P
All legendaries can be shiny when soft resetting.
in kanto