final cut studio 5.1 - pro applications update 2010-02

hi there

a bit confused here

i am using fc studio 5.1 with installed updates 5.1.4 - i am running leopard 10.5.8 on a mbp

right now i am in post of a 30min film - finally visuals edited

now working audio tracks

this is the first time i will take a project all the way to dvd and so will use the final cut studio soundtrack pro and. dvd pro.

until now i have only been using the final cut pro 5.1.4 part of the studio

i have been using logic express 8 to prepare music track. but need to explore how that works with fcp

my confusio is:

1- can i update fcs 5.1 using pro applications update 2010-02? it jumps all the way to fcp 7

2- do i need to install prokit update 5.1?

3. will this impact my project files at all? should i wait?

also

4. i don't have quicktime - do i need this? should i download "quicktime 7.7 for leopard"

thanks for help!

celia