I am giving my iPad to my wife. How do I change the current itune login which is my ID to my wife's itune ID so she can perform the updates or download any apps?
This is easily done form the iPad itself, you can just enter the iTunes or AppStore app on the iPad, scroll to the bottom of the frontpage, and press the button labeled "Apple ID:[your email here]". A box will pop up, where you can choose to log out of the currently logged in Apple ID. You will then be able to press the same button again, and then log in with your wife's ID.
Good luck :)
Go to the Settings app.
Scroll down to "Apple ID:firstname.lastname@example.org" and tap it.
Choose "Sign Out".
Your wife will be able to go to the same location and sign in with her Apple ID.
I hope this helps.
It would be better in the long run to deauthorise and reset the iPad to factory settings and have her "set up" the iPad as new from within her iTunes.
No cruft, all the apps (especially mail, calendars and iCloud integration) would be clean.