For only the Firefox referral, is this possible that I lable on top of the referal button like: Download Firefox - the best FREE web browser? Is this within the TOS or against?
You're recommending Firefox just over referal button - so it's against the TOS. However, take a look at that: http://explorerdestroyer.com/ (Meybe it's only question about the time when that site got banned).
Better to email Google and see what they say. I asked how we could promote FF referals on here and didn't get an answer, so I'm not going to put links up on my sites just yet.
I found this in google's blog see here http://adsense.blogspot.com/archives/2005_11_01_adsense_archive.html
Your interpretation is wrong. Read answer for that question carefully: Following, new_life asked about: As You can see, it's the same language G don't accept.