Fireworks -- you can see them from the boat dock by Gasparilla's (the QS place at the GF)
EWP -- you can see it. Not sure but I think from the beach area.
Monorail is on the 2nd floor of the main building. Walk there and use the stairs or elevator to get to 2nd floor.
Boat Launch - monorail is usually faster to the MK, boat launch is faster from the MK (has to do with the # of stops)
Poly - yes you can walk there. It's not that far. You can also take the boat launch (Poly is first stop) or monorail.
CR - you use the "resort monorail" to get to the MK, CR, TTC, Poly. It's the only one that stops at the GF. To get to Epcot, you take it to the TTC and switch to the Epcot monorail.
Hope this helps!
The GF is wonderful. Hope you like it!