Which investing programs should be avoided? What do people think about Sharebuilder?

i only have 1K, wanna put it away in a roth IRA, since im very young now.

for vanguard and fidelity you need 3000 and 2500 to start an account….are there any known ROTH IRAs (with low broker fees like vanguard and fideltiy) with a low initial investment (talkin 500-1000)

1. In both cases I can invest only after tax money.
2. I can withdraw my money whenever I want in both cases.
3. I can only contribute $5,000 per year in the roth IRA while I can contribute how much I want with a normal investment account.

So why would I choose to open a roth IRA instead of a normal investment account where I can invest how much I want?

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