Traditional IRA = tax break now, pay tax later. Roth IRA = pay tax now, tax-free later. Same contribution limit, mirror-image tax treatment.
Roth IRA features:
Contributions are not deductible.
You can keep contributing at any age (the same is now true of Traditional IRAs).
No required minimum distributions while the owner is alive.
Qualified distributions are completely tax-free: the account must satisfy the 5-taxable-year period (counted from the first year a Roth contribution was made) and the distribution must be made at or after age 59½, on account of death or disability, or for a qualified first-time home purchase. Non-qualified distributions can be partly taxable and may face the 10% additional tax on the earnings portion.
Moving retirement money: two roads.
Rollover: the money is paid to you, and you have 60 days to deposit it into the new plan or IRA. A distribution from an employer plan paid to you is subject to mandatory 20% withholding, even if you plan to roll it over. An IRA distribution paid to you is subject to 10% withholding unless you opt out. You can do only one IRA-to-IRA rollover in any 12-month period.
Trustee-to-trustee (direct) transfer: the money goes straight from one custodian to the other; nothing is withheld. This is the cleaner choice.