Well to answer your most direct question, the choice of Roth vs Traditional IRA is the same regardless of whether the money is coming from a tax refund or regular income. It all boils down to a question of whether the marginal tax rate of your current tax bracket is higher than your average tax rate in retirement. If yes, then traditional is better, if no then Roth. This means that if you're in the 25% bracket or higher than traditional is almost certainly a mathematically better choice, at lower brackets it's less clear.
However, I'm not sure your first option makes sense. You can contribute to a 2013 IRA until April 15th, yes. But that's because April 15th is the tax deadline. You'd have to announce on your 2013 taxes the money you contributed to your IRA in 2013, which kind of precludes you from using refund money to fund a 2013 IRA doesn't it? I suppose you could file, get the refund, invest, and then file an amended tax return, but don't forget that extra step.