Use the CWM from this thread:
And the tutorial from there. Then do a factory reset before and after flashing CM7 ROM. You don't need to root.
For ext4 partition you need a card reader, do...
@dany02 - Stop using Task Killers, they kill your battery life.
They will change your motherboard, same happened to my Galaxy FIT because of ROM Manager.
Just send your email/yahoo messenger or something similar and i will give you the apk files, but you still need to do a download for some games like PES, NFS Shift, they will need some extra things from the internet...
All google apps and the new market: Google Play.
BTW: is really fast, faster than before.