This is the fabled nerd conversation...
You're right, the enterprise isn't built for fighting, but I do believe that there are ships in the fed's fleet that could do this. You're forgetting the Klingons, though, they really are fighters, at least hand to hand wise, and we all know how terrible stormtrooper's aim is.
Plus if you've ever played Elite Force you'd know that voyager might stand a chance if they sent a guerilla boarding party.
Asguard the ships can fire behind, you know what the little phaser gun things look like? They're like lines on the ship, well they're all over the place, even on the tail of at least the enterprise D.
Plus we're forgetting the enterprise F's cloaking device, and that klingon warbird from ST 6 that can fire while cloaked. Ooooh.