Denon or Marantz? Home theater beginner.

I think you should just take a shot at whatever speakers are first on your thought list, and give them a shot. Otherwise you'll never know. Then, you can compare over time with other speakers in your system. Then, sell what you're not using later on on the used market. No problem.
Yeah, I'd lean to those Beemers over the paradigm Studio's (which I used to sell at a hifi store). Although I'm not familiar with those new B&W's - just speaking on past history).
I also personally have a pretty fair amount of experience with most of the receiver brands on the market. My experience as a hobbiest and industry guy both, is that the Denon's have historically made better sounding pieces at the entry to mid price points. They are usually musical, full bodied, solid sounding with good power (relative), are forgiving of less than pristine speaker choices, and are pretty well balanced. They also remain competetive - often surpassing - the other AV receivers on the market on up the price scale as well. Basically, it's hard to go wrong, and you can add an outboard amp to see what you're missing if you like.
I haven't had such good experience with the Onkyo's and Marantz's at the entry to mid levels. Their better pieces seemed to be on the top end of their linups, comparatively. Tastes will of course vary. But then I've had some rediculously expensive audiophile gear over the years. So I'm just referencing comparing relative to high end sounding components mostly here.
Another brand I think excells in performance (sound and video - which is where it counts) at the lower to mid price points ($350-$1200) are the excellent Harmon Kardon receivers. As and audio/videophile, you'd be barking up the wrong tree to try and convice me otherwise on these.
If I was looking at your choices, I'd be considering the 2310 - or even lesser- and adding an 0utboard amp, personally.
Another choice is looking at the EBay for the AVR354 Harmon piece. Sounds great, lots of power, EQ, HDMI1.3, True and master digital, lots to offer.
Anyway, that's my take.

Schwegs99

One point you make in your request for input here is that this effort is geared towards a 90% video involvement, and 10% music.

Films provide a lot of content that coincides with music, yet it adds to that with real world noises. Meaning speed and presence is key. Amps with good power reserves provide that result. So do speakers with good sensitivity.

The biggest or most additive piece to the HT puzzle, besides the image size and a cohesive sound field, is the subwoofer. Somehow you gotta figure in a very good sub for a more involving experience, into the speaker budget… if not immediately, very soon thereafter..

So some decision as to the degree to which you want the audio recreated is in order too, along with the interface options available now. Namely I’m speaking of HDMI.

Marantz/Denon, Onkyo/Integra, are IMHO more musically oriented appliances. Machines like Pioneer, and Sony in my exp, owning and selling them, are more adept at the HT aspect. They seem to possess more snap and sizzle than do the formers. More jump factor if you will.

Many people here are a bit more musically oriented and the posts to that effect are well represented by their voices on the receiver choices listed here already.

Warmth in the audio region can become a subtractive element if too much is added within the mixture.

Personally I feel you’re pretty hard pressed to go wrong with what ever you wind up selecting by way of receiver & speaker combos. I’d listen to as many setups as I could. Read as much online via the dedicated AV mags & forums, and look for flexibility, interface options, and local support if possible, along with items that fit into your budget to make your final picks.

The sub, the display, and the sound field are the key elements. Of the sound field, the front mains and center ch speakers (if a center is to be used) should be as congruent or seamless as possible. In fact if the prospective receiver will allow for a virtual or ghost center ch that will enable some funds to be freed up for say a better sub.

It will all work out for you I’m sure… so just put what you can now, where you can. BTW my first decent HT rig was Sony es AV receiver + BW 600 series speakers and Velodyne sub….. things have since changed as they always will.

What about the Onkyo TX-NR1007? Since im going to run 2 subs, would the Onkyo be better than the Denon?

+1 for Denon. I've owned Yamaha, Denon, Onkyo and Marantz. I respect Marantz and their products, but my Denon 4310CI is money.

Features and power are the normal added attractions as you move up in the line.

...and six months from now or less... there'll be another model taking the place of the one you buy now with still mo' stuff on or in it.... or so say the manufacturers.

Is a Porsche better than a Jaguar? A BMW better than a Lexus?

It all depends on how they feel to me and what I can afford at the time.

Past the esthetics their performance differences at that point will be measured usually in fractions.... not night and day lengths.

Please do get what you feel is best for you and not what some other person likes. That's always a very good approach... with just about anything. it's not life or death or anything near it, and I do understand the trepidation. IN the budget disclosed, good to very good is about all one can expect.