So I'm looking to rebuild the home theater system

@curiousjim - no, you do not need to put a load on them at all. In fact, putting a load on the unused channels will also put a load on the main power supply of the receiver. Just leave them disconnected.

Everyone has their opinions, but I found that the Yamaha line of receivers is the most natural sounding (no pun intended) - when compared to Sony, Onkyo, Integra, Anthem Arcam. Sony is very cold/bright sounding. The rest of the Japanese receivers are typical over-bright and too "solid state" sounding. Anthem is good, but I think it’s still a little too much on the bright side. Marantz is a bit too much on the warm/slow side. Arcam has it’s own sonic signature and many people like it. Arcam is definitely very refined, but to me it just does not sound as realistic as other receivers - mostly due to its Class G amplifier design.

Like phil9624 suggested, I would look at the upper lines if you can afford it. I recently had to buy a receiver for my mom and ended up getting the Yamaha RX-A2070. The two top models are 2070 and 3070. The 3070 was over $500 more and only weighed a couple extra pounds (not a huge difference in transformer size), so I settled on the 2070. Putting in a Furutech 10A fuse and upgrading power cord gave me very excellent results on this receiver.

Agreed.  Don't limit yourself to a 5.1 receiver.  They actually have much smaller power supplies and will perform less.  It's the size of the main power supply / transformer that matters.  example:

Yamaha 2070 - 9 channels - 37.5 lbs

Yamaha 1070 - 7 channels - 32.8 lbs 

Anthem MRX 520 - 5 channels - 28.2 lbs

The Anthem is the best 5 channel.  It might have better components internally, but it will not be able to compete in brute force power.  The larger transformers and power supplies of the Yamahas will be able to provide stronger bass/midbass, even at lower volumes!

Also, none of these receivers will be able to match a dedicated 5-channel amplifier, which can get into the 60-90 lbs area.

Just to keep things real - I never said Arcam or Anthem or anything else wasn't good.  The Arcam has its own unique sound and it is not my preference.  I equated Class G to be similar to Class D in a sense because the higher power supply is "switched" on and off just like a Class D amp.  The Arcam sound also has a very similar clean tone to Class D - which for me does not give a sense of life or realness - Conclusion is that it's lacking ultra high frequency response and "air".

I have not "demoed" or listened to Yamaha and others at Best Buy (which I agree is not the best place to listen).  I have personal experience with Yamaha receivers and I like them, even though I would not buy one for myself. 

Finally, there is a certain point of view that most dealers have which is to promote the gear that they sell.  It's a commercial enterprise, so it is always in their best interest to buy something they have - regardless of their denials.  Otherwise, they would commonly recommend something they do not sell.