I have a TSP Gov acct account.. I will be 70 yrs old Nov 12. I do not need the money right now. How can I shelter it for my wife. How can I avoid paying taxes on withdrawalls?

Like 401(k)'s and traditional IRAs, you must start taking minimum distributions from the TSP by April 1 of the year following the year you turn 70-1/2, so for you that means by April 1, 2013. Distributions are taxed as ordinary income, and the tax can't be avoided. About the only thing to consider is perhaps rolling the TSP account into a Roth IRA - Roth's do not require minimum distributions so this may be beneficial if you're concerned about leaving adequate funds for your wife. But as you may already know, converting to a Roth requires that you pay income tax on the rollover, and that tax should be paid using funds from somewhere other than the TSP itself. So you pay taxes now and then all future earnings and distributions are tax free (assuming you maintain the account at least 5 years before taking any withdrawals). This may be something to consider if you have the cash available to pay the taxes and don't need the money for at least 5 years.