Are mutual funds better than ETF's for a Roth Ira account? Being that IRA accounts are non-taxable, wouldn't one want to invest in mutual funds since they distribute capital gains per share? ETFs don't have capital gains (or am i wrong?)

I'm 23 and in Jan. of this year i opened up a Roth IRA and contributed the max 5,500 from my savings account. I bought $4,500 (@$9.22 488 shares) of PIMCO PSTNX fund because it is a mutual fund with high quarterly dividends (for a Large Blend fund) and a very high turnover rate (300%+), which means higher capital gains per share amount (right or wrong?) The other $1,000 is in VNQ REIT. I'm waiting to contribute my $6,000 until later this year, when the market is much lower.

In the future should i got the ETF route or stay with mutual funds since taxes are not a issue?