Hi, you'll have to follow the directions in the jailbreak (hacking) forum section to install the 4.3 iOS. When you do it is going to take away your jailbreak, so, you'll have to jailbreak again. Before I upgraded to 5.1.1 I took screen shots of all of my icons, especially the jailbreak ones, and a snapshot of the Settings app showing the section of the jailbreak tweaks. I copied those to my computer so I could reference them. Then I copied my Winterboard folder so I would still have the theme I put together. I have yet to find a utility that will save the data from certain jailbreak apps. You reinstall the app from cydia and the game saves or settings are no longer there. There may be an ap for that but I haven't found it.
I though long and hard about upgrading to 5.1.1. I went for it so I could upgrade two of my iTunes music apps. I don't have many cydia apps and tweaks, so it wasn't much of a bother. One of the groovy things about the purchased apps from cydia is they are registered that I purchased them. I didn't have to remember the paid for apps, nor pay for them again. I just re-downloaded them.
My iPad 1 is wifi only and 32gb.