I'm confused and sorry for this n00bish post.

Can i use iBrikr to jailbreak my fresh unactivated iphone with iTunes 7.4.x on WINDOW$? Is this safe?

Cost of this info is to give me a + on the REP (the thumbs up on the left under my name )

i think you will have a problem; best way is to use winstaller (search for it in the forum). you need the winstallerGUI that is in the program directory, click jailbreak .. wait for it then close it and start using ibrickr

Here is another noobie doubt... I read that u need fo have iTunes 7.3.x in order for iBrikr to work. After having an iphone jailbroken using ibrickr with itunes 7.3.x can u sync your iphone with iTunes 7.4.x on other pc/mac? Can you update iTunes 7.3.x to 7.4.x in the same pc you´ve done the jailbreak and still be able to sync the iphone?

Yes! infact iBrikr works in iTunes 7.4.x You do not need iTunes 7.3.x.