From what I saw, only a few people got blown into space, not the entire crew. It is certainly possible the ship could defeat the four ships and move off, but I doubt that is the plan.
More likely, Archer has convinced the non-rertillian Xindi to at least halt their attck. Daniels never says that ALL the Xindi races survivbed, he just said Xindi join the federation, it is just as likely the 4 races will kill off the aggressive reptiles.
T'Pol's behavior was already explained, and I knew they would fall back on something stupid ( to see what, read the spoiler that was already linked earlier in the thread.)
This whole story arc was lame, I knew it would be something pointless, as most time travel stories are. Once the Xindi are convinced to attack earth, the easiest course, outside of going yourself, is to send a ship from later in the time stream, that the Xindi couldn't handle, say Kirk's enterprise. Of corse, they will make up all kinds of lame reasons why you can't, I'm sure.
I'd still like to see the show go on, minus these stupid time travel things.