Druids aren't strikers, but some of the wild shape powers are striker-ish (in terms of melee).
If you're looking for a druid that can kick ass with ranged spells, however, you need to multiclass. The invoker is a Wisdom primary "controller", with the wrathful invoker having some striker-lite abilities. I'm not aware of any specific Wis-based ranged or area strikers that you could multiclass with, though.
No idea - why would anyone want to when you could just as well play a different class that deals insane amounts of damage without having to 'munchkin' it?C'mon. Someone must know how to munchkin a Druid?
Yeah, my advice would be to go to the WotC forums. http://community.wizards.com/forums/77391 All the non-trivial 4e forums are still up and live, you can ask in Charops, [...]
While I don't recall specifics, I did once gave a 4e 14th Druid that was matching the strikers in our party for damage.
Warning: if you ask the CharOP guys, be sure to have a thick skin. They are not the nicest guys with their word choices. (When they belittle you that you want to make a druid a striker)
Meh, if you just go in and say "look, I'm going to be running a druid, this is a given, how can I make it as much of a striker as possible?" you aren't going to get a lot of guff. Sometimes there's that smartass that will say "convert him to ranger" or some silliness but you'll basically just get pointed at sound advice. The jerkiness really comes out when people wander in there and start insisting that their totally lame charop concept is hot stuff or trying to tell everyone that some well-known optimization path "doesn't work" or something equally inane. THEN they're merciless.