Are the contributions to a traditional IRA taxed differently than the earnings when withdrawn and/or are they both considered taxable income when withdrawn? And at what rate? Capital gain or regular income tax?
Contributions to a traditional IRA are treated as ordinary income when they're withdrawn, as well as the earnings.
The IRA withdrawals are not subject to FICA withholdings (Social Security or Medicare). Other than that, they are treated the same (as ordinary income).
Edited - to clarify per comment below.