3G won't update to 4.2 software

i have an iphone 3G running OS 3.1.3, imac 10.5.8, and itunes 10.4.

when i try to update the ios on my iphone to 4.2, it stalls on the backup, with minimal progress on the blue status bar. i hae 7.08G remaining on capacity on the phone.

any thoughts?

thanks!

How long does it stall, and have you backed it up before? If you have never backed it up 3.1.3 can take 8 hours or more for the first backup. If you have backed it up successfully recently you may have a corrupt backup. Deiete the backup (iTunes Preferences, Devices) and try again.

it syncs when i connect, and is done in a few minutes. i also did a manual back up, and it was done just as fast. do you know if i need to update my mac OS to 10.6 first?

truthfully, the only reason i want to update my phone is for some of the software that's available. otherwise, i don't have any issues or complaints. it's an old 3G, so it is what it is. but i also don't want to add any issues by updating the OS.

You need 10.5.8 or later to install iTunes 10.4, and 10.4 is required to update beyond 3.1.3.

i'm on 10.5.8, and i have itunes 10.4.1.

in the meantime, i'm looking into updating my OS to 10.6 and then lion. (i believe i need to take a 2-step update on the mac for the OS update.) i saw a free download on cnet for 10.6.8 - why would it be free?

Yes, you must be on 10.6.8 to update to Lion. If you saw a free download it is pirated, and has also probably been hacked.

that's what i'm afraid of. i saw the old 10.6 on the apple store's website, and it says ships in 1 - 2 weeks, so i was hoping for a download that i could purchase. but can't seem to find a reliable place. funny thing is some of my software is more up to date than what comes with snow leopard (safari, itunes). will this be a problem going backwards? a bit frustrating that i can't make a big leap to lion.

Lion is available only through the Mac App Store, and that is only in Snow Leopard. I got Snow Leopard for my wife's computer at an Apple store.