AV receivers

My parents recently purchased a widescreen TV + VCR + DVD player in a package deal. I sat there looking at the hi-fi system next to it, which has five speakers (though not 5.1 - there’s no sub, at least not yet) and wondered if it could be hooked up to the TV to provide surround sound when watching movies etc.

Now a mate has a similar thing sans hi-fi (does have 5.1 setup) and uses an AV receiver to hook everything up.

I thought about this but the problem is that the hi-fi is quite old (~10yrs I’m guessing). It’s an AIWA system with tuner/turntable/equaliser/amplifier/5-cd changer/tape deck.

Because it’s quite old, I don’t know if any Av receivers would support it. The hi-fi has Dolby Prologic (guessing its version 1) and DSP.

Anybody able to advise as whether I’d be able to hook it up to a suitable AV receiver and, if so, which one?