[jujumantb]

Decent choice on equipment there, I wouldnt change anything there.
Amp....

Well lets start with the subs, having 2x dual-4 ohm subs means each can be wired to 2 ohm, or they can be wired both together for a final 4 ohm load (or 1 ohm but we wont need that). Now if you only want ONE amp to power both the 6x9s and the subs, this is what I would do...

Get a decently powerful 4 channel amp and wire one sub to each rear channel, the amp will put out max power @ 2-ohms per channel, which is what each sub is at. Then wire each 6x9 to each front channel.
Kinda hard to explain feel free to ask more.

BTW I know FOR A FACT I am easily the most knowledgable about car audio on here so you can take my advice.