Moving from Mac to PC... several questions on HW and SW

I've been following dpreview forums on and off for years; however this is my first post.  I'm just an amateur photographer with a Nikon D7000 and a few prime lenses.  Most of my pics are of the kids playing sports or vacation shots; however, I do like to get out and take landscapes or urban architecture shots.  I love taking pictures, but I've struggled to embrace the post-process side of the hobby.  It just takes so long and the all the different software available is overwhelming.

After years of struggling with a 6 yr. old iMac and Aperture (both of which I hate), I've decided to move to a new PC as well as new software setup.  So in essense, I'm starting over.  I really want this to change to rejuvenate my enjoyment of photography and make the back end easier while also teaching me the methods to get better results.

I built a PC with the following specs:

• OS: Windows 8 Pro 64
• Motherboard: Intel DZ77GA-70K
• CPU: Intel Core i5 K-sku (Sandy Bridge)
• Memory: 8GB
• SSD: 120GB, SATA 6 (OS and Programs only)
• HDD: 2TB, SATA 6, 7200rpm (Data)
• NO OPTICAL DRIVE (I have access to a friends USB optical drive if needed)
• Monitor: 27" Samsung

The PC is up and running but I haven't installed any photo software yet.  So here are my questions...

1. Do you think my PC has decent specs  for photography? I'm most curious about the 8BG of RAM. Is that enough? My biggest pet peeve about the iMac and Aperture was the latency involved with scrolling from pic to pic.
2. I was thinking to install Lightroom 5, but I'm confused about the difference between that and Elements 12. Are they competing products (i.e. both claim they can organize and edit photos) or complimentary products (i.e. work together)?  I always thought Lightroom was for organization and Elements was for editing. 
3. If not the Adobe products, are there other software products I should consider for organization, editing, etc?  Also, I'd like to learn to do HDR.  Is there ONE piece of software that can do it all. 

Thanks for your help!