I am a newbie to this forum.

I hope the gurus could offer me some advice.
I have recently bought a Sharp LCD TV (LC-42A77M Aquos Full HD) and using an old Sony STR-DE425 (Home theater in a box back in 1999) 5.1 AV receiver.
This set came with 4 satellite speakers, a front and a subwoffer. The speakers are 8 ohms (100W input max 120W). The subwoffer has a 160mm cone 50W power output.
I intend buying the Pioneer VSX-819H-K AV receiver. The receiver is also sold in a home theater package consisting of the Todoroki speaker system. The Todoroki speaker system uses two 3 way front tallboys, centre and two satellites and a 30cm active subwoffer. My Sony woffer has an on/off switch on it, is that an active woffer?
My question is can I just buy the receiver alone and use my old Sony speakers?
The satellites are very neat in the living room.
Thanks