It is on 3.2.1 so now what?
So you'll need to plug it into a computer with iTunes and an internet connection, preferably the same one your brother used when he got it, but otherwise and computer will do.
First it will probably tell you an update is available. Tell it just to download for now.
It will ask if you want to "Erase & Sync" and if you want to keep everything on there - DON'T - do that.
After that right click the iPad in the sidebar of iTunes and create a backup.
After it backs up, left click on the iPad in the sidebar so you see information about it. Somewhere on there it will say something about a software update being available, click and install it.
After it updates your iPad will ask if you want to restore using iTunes, to that say yes and it will restore all the apps and settings that you had on there.