Having been through a similar experience, here's a view from someone who is also new to road cycling (though not new to cycling as I've been riding hybrid(s) for over 10 years). I've had my new road bike for about 3 months.
Forget about finding a right fitting bike. I don't think this is possible as we are too new to the road bike to know what feels right or wrong. We could sort of guess what feels comfortable, but after couple of returns and 1-2 month later, I finally found the right bike.
There are just too many variables to consider and it took many adjustments on my own to fit the bike to my body shape or to my liking. Even couple of centimeter of seat position, seat angle, seat post height, handle bar width, handle bar position/angle, and cleat position can change the dynamic of your ride. For example, after riding few miles, I've noticed that my quad was getting extremely tired - and my seat position was optimized by the LBS. When I've raised the seat post by few centimeter, I was able to off load some of the quad force, into the calve and my speed increased full 1 additional mph.
So as someone new to the road cycling, find the one that fit reasonable well and make sure that your LBS have a return/exchange policy.
As for choosing the bike, its a compromise between your ideal brand/image/cool factor and value. I chose the bike based on my impression of the brand (cool factor? - it matters) and value (I bought a closed out model because it had a better component/frame). While everyone talks about why this or that components is better, I couldn't tell you the difference between Tiagra/105/ultegra, etc. If it shifted, then I knew it worked - nothing more.
Although experienced riders will know more about aluminum vs composite - at our stage of road cycling, everything is arbitrary. Questions that went through my mind at the time is - composite looks more sexy (stupid reasoning, but at our level, impression does matter), do you want more lighter frame (in my case, carbon was heavier than aluminum model I was looking at), etc. So buy the brand and model that your money could buy.
There are other factors to consider - for example, I didn't know what compact/double/triple gearing was. When test riding at the parking lot, those consideration doesn't really come into play. Again, we can only go with what others say and don't have a experience enough to select what we want.
Don't forget to put extra money away for shoes and a saddle. From my experience, the saddle was the most important part of my riding experience. I've must of tried 10 different saddles and finally found the right one. Without that right saddle, I probably wouldn't be into cycling so much. The right shoe is also critical item. You have to be comfortable to enjoy the sport. Unfortunately, shoe is one item that my LBS didn't allow return after its worned. So I now have a one useless shoe sitting in my porch
The bike I've finally chosen was/is Fuji Team, which is a full carbon/105/ultegra. I didn't choose this bike because of its name/components/carbon, etc. I bought it because it fit and was on a closed-out sale, which is always a good reason. The bike I really wanted was specialized Roubeux Comp (I think, it was a aluminum/carbon fork bike) but didn't want to pay full MSRP.
Again, based on my recent experience, it didn't matter which bike I chose as I would of done exactly same - spending about 2 months getting to know the bike and adjusting every part that is adjustable to find the sweet spot. Now that bike is fairly optimized to my liking, I'm really enjoing the ride.
Hope this helps.