Connecting PC speakers to Home Theater Setup

I have this speaker system:
Creative Inspire P7800
hxxp://tiny url.com/njynoj
(hxxp=http, remove space)

But I no longer use them for my PC, so I was wondering if there was a (cheap) way of using them in a home theater setup?

I have a Sony CRT, possibly with an optical audio out, but most likely a coaxial audio out. I also have a DVD player, and an xbox 360 (optical audio out) that I would also like to use in this setup.

So I'm guessing, if these PC speakers are even compatible (cable-input-wise) with a home theater setup, that I would need a 7.1 AV receiver in order to connect the 7 speakers, and 1 subwoofer via RCA adapters? (since these are auxiliary inputs, and I need instead the Red / White audio inputs)

And from there I could just get optical audio / coaxial audio cables running from the TV, DVD, or xbox 360 to this AV receiver?

What I'd like to know is if this is even viable, and if so what receiver I should look into for such a situation, considering price as a major priority.

This apartment-bound college student thanks you

Thanks for your input, you saved me time and money.
I guess I'll need to find some other way to use these speakers