Just a quick note, doesn't look like English is your primary language, but to be clear, you want to upgrade to Ice Cream Sandwich from Jelly Bean?
If you went from Jelly Bean to ICS, you would be DOWNGRADING. Jelly Bean is a newer version compared to ICS.
Here's the order:
Android alpha (1.0)
Android beta (1.1)
Cupcake (1.5)
Doughnut (1.6)
Eclair (2.0–2.1)
Froyo (2.2–2.2.3)
Gingerbread (2.3–2.3.7)
Honeycomb (3.0–3.2.6)
Ice Cream Sandwich (4.0–4.0.4)
Jelly Bean (4.1–4.3.1) <- you are here in the OS hierarchy.
KitKat (4.4–4.4.4)