Traditional IRA

You have three options: 401K, traditional IRA, rollover IRA and ROTH IRA

401K: There are limited options to invest in 401K plan.  You cannot invest in individual stocks, and you have a limited number of funds to invest.  I'd stay away. 

Traditional IRA:  tax free now, withdraw with income tax after 59 1/2.

rollover IRA: same as traditional IRA, but you can send money in rollover IRA to a 401K plan later. 

ROTH IRA: pay tax now, withdraw without tax after 59 1/2.  

I used to advocate ROTH IRA, but someone commented that if you can deferr tax, why would you want to pay tax now? Nobody knows what's gonna happen, and the present value of money now is more than the present value of the same money in the future.  

So my recommendation is to rollover the money to Traditional IRA.