[root] star/upai n7100+

Hi everybody !
I'm french so sorry for my bad english.

I bought a STAR/UPAI N7100+ with a MT6577. It is very beautiful and usefully !

On a chineese website, I download .rar file with many files :
boot.img
cache.img
DSP_BL
EBR1
fat_sparse.img
logo.bin
MBR
recovery.img
secro.img
system.img
uboot***.bin
userdata.img

I would like just root without change my phone.
If I download every files into the phone, it is root.
But which file does the "root" for staying my data and applications.

I would like too add "CRT animation" but I don't know how do.

Thank you.