I forgot the most important question. Budget?

I wouldn't be concerned about 7.1 right off the bat. You could make sure your AV receiver handles it for later experimentation though.

Amp vs. Receiver.
I'd go with an AV receiver that has the features you want within your budget. This allows you to grow as your needs change.

Room size.
This is an average room size. Anything in the axiom line should fill it nicely.


Speakers
There are many great speaker options but since this is an Axiom board and I'll attest that you definitely can't go wrong with them, I'll use their models as examples.

Light Budget - stereo
a Stereo M3 setup. I don't own them but they are said to be a great all round speaker that performs well without a sub.

A REALLY nice 2.1
M22 fronts with an EP350 sub.
Again, I don't own either but the M22s are acclaimed for their amazing accuracy and the sub will fill in deepest LFE to cover off the entire musical, movie and gaming spectrum of sound. Sets you up for a great 5.1 system later.

Amazing 5.1 (or next step after above)
Keep the M22 Fronts and the sub. Add QS8 or QS4 for surround sound.

Options--
1. Appease the desire for floor standers by replacing the M22s with M60s or M80s. Or do this down the road and re-use the M22s as the rears for the ultimate 7.1 system.

2. The more 'Obvious' choice.
Axiom makes a very nicely reviewed PC speaker setup that actually includes an amp and an optional subwoofer. it's everything you need in one package. I haven't used it but others here rate it very highly. By sheer size and design it kicks the ___ of your big box store PC speaker systems, for sure.

Others will chime in with other ideas and substitutes I'm sure. Again, it all comes down to budget.



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