A few questions in purchasing a new MacBook Pro

Question

I have recently become a full Apple fan (I have been a PC person for nearly 28 years), and am in the process of purchasing a new MacBook Pro (as my old HP Pavilion is on it's last legs).  As I am in this process, I am trying to decide which MacBook Pro fits my needs, and thought the Apple community might be able to help.  Here are the things I am looking for:
1)  I did recently finish graduate school, and although I have a steady income, I would prefer to still be economical with what I spend - I don't really need the top-of-the-line model (as much as I'd love the retina display screen), but I do want to get what will fit for me.
2)  I typically like my laptops to last 4-6 years.  Here is what I typically use my computer for:
      -I don't do a lot of gaming no my computers
      -I do like watching streaming videos or dvd's a lot
      -I do a lot of photo editing - I currently use Adobe Photoshop Pro, but don't know what I will use on the Mac yet.
      -I do a lot of reviewing of photos as well
      -I also have a large media library (audio and a little video) - incidentally, I DO need an optical drive/cd drive so I can import my music purchases.
3)  My computer is currently a 17" screen - while I love the size of my current screen - the price of the larger screens with the MacBook Pro's is almost prohibitive.  I'm currently debating betweent he 13" and the 15".  This brought up my final question:
     The 13" MacBook Pro offers the following for processors:  Section 1:  Up to 2.7GHz quad-core Intel Core i7 processor; however a second section stated it had an "2.5GHz dual-core Intel Core i5 or 2.9GHz dual-core Intel Core i7 processor".  I'm not sure why the 13" had both of these listed as possibilites (perhaps it's in the customization of the computer?)  ***Actually, as I am reading the information further, it seems that the quad-cores mentioned on one of the pages are not available in the 13"***
     The 15" offers an "Up to 2.7GHz quad-core Intel Core i7 processor (it looks like it's a 2.3 OR 2.7GHz quad-core processor respectively)"
I understand that most current programs are written only for a "dual-core" processor, and as such a dual-core processor will outperform a quad-core processor currently; however, once programs start getting written for quad-core processors, those computers will take a drastic jump forward in processing speed.  To be honest, I am not sure which processor I need both in terms of what I'm doing now, and also in terms of running well in 4-6 years.  What is the difference in the i5 and i7 processors - is the dual/quad core processing the only difference?  Further, what difference is the 2.5 vs 2.9 GHz processor (or for the 15" screen the 2.3 or 2.7 GHz processor)? 
I know this was a long winded question, but I want to make sure that I get the most for the money I spend, and that it will do what I need it to for the next several years.  Thanks in advance for any help/guidance you all can offer!

Answer 1

My buying advice - the 'entry-level' new 15" MacBook Pro. Take a look at the specs. It's a wonderful machine - and you can upgrade RAM and HD to fit your needs without voiding the warranty. I don't know of any apps that I currently run that can't take advantage of the quad-core, and almost everything is 64-bit now.
I'd used the money you saved from not buying an out-dated 17" and put it into software. If you're transitioning from Windows that can add up quickly (which isn't to say you can't run your Windows apps using Boot Camp or a VM like Parallels.
Just my opinion - but if I could buy anything I wanted right now, I'd go with one of the upgraded 15" non-Retina MacBook Pros.
Clinton