I'm lazy I know... Need advice...

[baasmartin]

Hi, I know I'm lazy, and i should go look myself for what i need, but all these things are confusing me. I need help.

I have a 32" samsung lcd tv in my room, with a ps3, and then a computer.

What I want
I want to hook all of these up with a nice surround sound system, so when I play blu rays on the ps3 i want surround sound, and if i play movies from the pc, i want surround sound.

Basic, I want a sub with 5 speakers, room is quite big so i can accomodate. But in the other hand budget is a bit low.

What i have:

I have just normal pc speakers, and for the ps3 a hdmi cable.. and i have sony front l/r speakers, center, back l/r and a subwoofer which a rated 3ohm, but they have connectors on them for the dvd player that came with them. the dvd player went walkabout.

What confuses me now:

There is talks about an av receiver? what the hell.. and impedance vs power and what not. I just want a simple answer. I dont want to buy a dvd player beacause i've all ready got a ps3 and pc to play the discs. and actually i dont want to use thes speakers anymore. and whats an optical cable used for coz there is a jack a the back of my tv and ps3. and how do i connect the sound from the pc to the tv or surround sound?

generally i know just buying a 1set in the shop is usaully the most convenient but not always the cheapest.

Could anyone point me in the right direction here... im confused

and what sould i go buy, like
1 an optical cable
2 surround sound
3 wires to conect them

HELP>>>>