vanguard or fidelity, both are good.

Withdrawal for the first home purchase is ok without penalty. but you'd better not to, as you can not put the money back after withdrawal.

What does this mean?  My IRA gets over when I withdraw some money for the first home purchase?

Technically speaking, you dont choose roth or traditional IRA. they choose you.

Traditional IRA has an income limitation and if your have high income, you might be phased out.