dynomot is right when he says there is no substitute for reading.
However, lets point you in the right directions...
I am wanting to update my phone with the new icecream, my phone is currently rooted and I am running gingerbread.
I have no idea what I am doing so some detailed guidance would be much help.
Since you are rooted you cannot update via Kies. However you can update manually via Odin if you wish to go for a stock Samsung ICS ROM. See posts
#1 and
#2,
here.
To update via Odin, pay careful attention, but not exclusively, to the section entitled, "
My firmware is not eligible for ICS yet but I want it now!", in post
#1. The latest ICS firmware is, currently,
LPG providing that you want an English/European language.
This will un-root your phone as you will be flashing the stock kernel that comes with the stock ROM.
Since you have already rooted your phone once, this will act as a refresher for you to re-root again.
Rooting Galaxy S2 - A Dummies Guide.
There are other methods of moving to ICS, using custom ROM's and flashable .zip files but I would not recommend them for the reasons laid out in post
#1,
here.
also the software the new s3 has is that icecream too? if not what is it, and is it possible to have that on the s2.
The SGSIII was released with Android 4.0.4 and it is not a simple matter of copying the firmware from it to the SGSII as they are entirely different handsets. However, many custom ROM's claim to offer some of the features of Android 4.0.4 and you can obtain some of the app's from the SGSIII from
here and
here for your phone
after you have updated to ICS.
I would now suggest grabbing a coffee or a beer and start reading up on those links, thoroughly and carefully as you have a lot to learn and there are no shortcuts I'm afraid.