Thing is mate Razor shouldnt be watched before the end of season 3 an the web isodes, otherwise you wont get some of the references. There is a second BSG film planned an there is Caprica to look forward too aswell.
I have got a encyclopedic knowledge of all BSG episodes, an have seen each on a good 8 or 9 times. Also start at the very begining unless you get who caprica 6 is from the first part of the mini series the parts on colonial one wont make much sense.
There is a few great bits that most peole wont get in part one, also you will miss the "It has begun" sceen right at the begining, that was just so well done.