Avoided Bose? That's better than winning the freaking lottery! lol
Seriously though - Bose systems are a horrible rip-off and you are so, So, SO much better off now that I can scarcely explain it.
Anywho - you've been given the standard "catch all" advice of "go out and listen" and "internet direct companies are a great value". I do not disagree with this advice, but I am not a fan of giving it.
The reason is because - how do you know for what you are listening? You might LIKE the way a certain speaker sounds at the store, but that doesn't mean that it is accurate.
But more importantly, your equipment and your room are equal partners when it comes to sound quality. Room acoustics play just as large a role in the sound that you hear at your seat as the speakers and receiver and source that are being used to create the initial sound. So hearing a speaker at a store does not really tell you what it will sound like once you get it home!
Certain speakers work particularly well in certain types of rooms. There are many different types of rooms, which is why there are many different types of speakers!
The goal is to buy speakers that will work well WITH your room. You can have your speakers and room work together, or you can have them fight one another - obviously, if they are working together, that is better
So...we need to know about your room!
You have a good budget. We can recommend several options. But your BEST choice is going to be determined by your room.
What are the basic dimensions (width, length, height) of your room? Is it a closed room or does it have openings to other rooms of the house? Do you have carpet? Do you have thick curtains? Do you have lots of plush furniture? Do you have an acoustical treatments on your walls? Bass traps?
How far away is your seat from the speakers? How is your furniture set up within the room?
Diagrams and pictures are a HUGE help - but please describe your room in as much detail as possible. The more we know about your room, the better we can recommend speakers that will work particularly well within your room.
Also - do you strongly expect to be taking this system with you to another room in the future?
You avoided Bose, so you're already ahead of the game! Now it is time to maximize the performance you get for the price that you pay and in order to do that, we need to know all about your room
To answer your question about the receiver:
First and foremost, the receiver is your "hub". All sources get connected to the receiver, so naturally, you want your receiver to have enough connections that it can accommodate all of your sources and have a few inputs left over for possible future sources. You also want it to be able to handle all of the various sound formats that might come its way.
The receiver plays a significant role in the sound quality. First - it has to be able to decode and process the various sound formats. When I say "process", there are many things that a receiver might do to any given signal. It will perform bass management, it may expand stereo sources to 5.1 speaker output or expand 5.1 sources to 7.1 speaker output. It may also have "room correction" software that will attempt to alter the signal to correct for acoustical anomalies in your room.
After all of that processing, it's down to the amplification. Some speakers require more power than others. The worst thing that an amplifier can do is "clip" - which basically just means that it runs out of power and cannot play the sound as loudly as you would like. But before any amplifier "clips" it will distort. And, naturally, distortion is a bad thing! So you simply want to buy a receiver that has enough amplifier power to adequately drive your particular speakers to volumes as loud as you would like.
The room makes the biggest difference - the speakers make the second biggest difference. So first, we select speakers that will work well in your room and then we select a receiver that will work well with those speakers...make sense?
So I'll be happy to give you some recommendations once you write back to us with details about your room!