To assist in tracking nondeductible IRA contribution, these were transferred to Roth. Is this a nontaxable event? Do earnings on these nondeductible contributions have to be transferred?

Distributions from IRAs are different than you might think. Let's say you have a $10,000 IRA in which you have a $2,000 basis because of a nondeductible contribution one year which you reported on a Form 8606. If you withdraw $2,000 from your IRA, it is treated as if it is proportionately return of basis ($400) and distribution of taxable amount (previously untaxed earnings and deducted contributions) ($1,600). That is, 20% of the distribution you take will be treated as return of basis and therefore non-taxable. The rest will be subject to income tax.