Zapdos-Very good moveset, just keep in mind that some people consider HP legendaries "cheap"
Forretress-Good, Reflect is an option over Toxic.
Meganium-Very nice, but I would go with Razor Leaf instead of Body Slam.
Blissey, Skarmory, and Suicune's movesets are all great!! You don't need to change anything on them IMO.
Overall: Very good team, your movesets are great, the only real problem that I see is the one that you already have mentioned, the 3x weakness to Fire. Outside of that, everything else looks pretty good.