You can OPEN whatever accounts you wish, you can only FUND your retirement accounts (i.e. IRA + Roth IRA) up to the annual contribution limit.
Any given individual's annual contribution limit for 2013/14 is $5,500 ($6,500 if you are older than 50).
Remember you can open and fund any account (as if it were done in the previous year) prior to the tax filing deadline of the given year. E.g. You can still open 2013 accounts until you file your 2013 tax return.
Examples:
During 2013 you open an IRA and fund it with $2,500. You can open a Roth IRA in 2013 and fund it $3,000. For a total of $5,500 (contribution limit).
During 2013 you open an IRA and fund it with $5,500. During 2014 you open a Roth IRA and fund it with $5,500.
Your spouse is allowed to do the same, effectively doubling the contribution limit. Mind you your contributions to not exceed your income in the same taxable year.
Assuming you are filing jointly this "doubled" limit can even be met even if only one spouse has earned income!
AS SPOUSES, the total combined annual contribution limit is "doubled." So $11,000 normally and $13,000 if you are each 50+ ($12,000 if one < 50 and one 50+).
All this is to say, as an individual you are allowed up to $5,500/6,500 per year divided among whatever accounts you choose and up to $11,000/$13,000 per year as spouses (two individuals).