Generally, a Roth IRA is probably the best bet over the long-run. There are many advantages to a RothIRA. If you have significant growth, the growth won't be subject to federal taxes (whether or not it is subject to State taxes varies from state to state. You can always withdraw your principal. Furthermore, especially at this point in time, a Traditional IRA is, I think, a bad idea. The national debt is at very high levels and inflation (increase in monetary supply) is running at 10-15% annually; all this means a likely chance of much higher taxes later on to pay off all of our national debt. Tax-levels right now are relatively "low" <cough>, and are likely to go up no matter what.
I would recommend opening an account with either Fidelity, Vanguard, or T.R. Price. These are companies of solid long-standing reputation. Fidelity offers a huge array of mutual funds; Vanguard, index funds with unbeatably low expense ratios; and T.R. Price, some excellent funds.
This website lists State-treatment of Roth IRA distributions. It also says which States have no income taxes (not too many of them, unfortunately).
PS: You definately do not want to have your Roth IRA invested conservatively, as is your money in your bank. This is money that should be invested for the long-term (retirement); thus, you should be willing to accept more short-term volatility in exchange for greater long-term profits.