I need help updating my iPhone!!

Question

Okay...I have a weird situation here.  I've called my local Apple store and Googled until I'm blue in the face and I cannot find any answers.
Please please please...I beg someone here to help me.
Here's my situation:
I have a MacBook...a very old one that has NEVER been updated.  I know, ignorant on my part, but that's besides the point.
It is running on a very old version of iTunes.  And it's been so long since I've updated my operating system that it wont let me get a newer version of iTunes.
When I tried to plug in my iPhone soon after I got it, I got an error message along the lines of, "This device is not compatable with this version of iTunes."
So...I tried to update iTunes, cant do it, because my OS is so out of date.  I dont even know what OS I'm on.  It's way before Leopard or Mountain Lion or any of that stuff. Whatever came with the MacBook when I got it 4-5 years ago.
My iPhone is STILL running on the same version it had when I got it a year ago. (4.2.6)
Nothing has ever been backed up...simply because I cant.
Now, my question is...
Can I plug my phone into my moms PC?  I dont necessarily care to back up my contacts/pictures up on her iTunes.  I have over 4000 pics on my phone and I'd hate to clog her PC up with all that. I just need to use her iTunes in order to update my phone to the most recent version.
Her computer/iTunes has never been plugged into another phone (she still uses a flip phone). So my iPhone would be the only device that has ever been hooked up to her PC.
What are the risks here, if any?
Is this possible?
Any help is MUCH appreciated.

Answer 1

If the iTunes on your mum's PC is the most up to date you should be fine.
Simply plug the iPhone in, make sure that if you have a keypad lock on that you unlock it. Then when iTunes recognises the iPhone, right click the little picture of the iPhone and press backup.
Once it's done that left click on the little phone icon again and it will bring up a summary page on the right. Click the 'Update' button and let it do its job.
Now when that is done, on the phone just check to see if all your data is still there. If it is you can just delete the back up from your mum's computer by navigating to C:\Users\<your mum's username>\AppData\Roaming\Apple Computer\MobileSync <---- there will be a folder in there called "Backup", just delete that folder.
If it isn't you will need to use a third party app to retrieve the data from the backup because I believe that iOS 6 is incompatible with iOS 4 backups, well at least 5 was anyway.
If you have lost your data on your phone, don't delete the backup data from your mum's computer, I'll help you get it back on your iPhone before you delete it.