The iShares index ETFs are essentially as good as the Vanguard ETFs. There's not enough difference between them to justify paying extra trading fees for Vanguard.
As to which funds, how does your investment policy statement say you should divide your money? What percentage of stocks, what percentage of bonds? What percentage of those things should be US-based vs. international? You need to decide that first. Once you have done so, the particular fund choice isn't that hard.