Macbook Pro Retina - Really struggling on storage options

Hi

I converted over to Apple in 2011 with an iPad, a macbook Pro and an iPhone.

As a long time PC user, it took me about 18 months to convert but, once there, I was fairly happy.

I've always struggled with the iPhotos systems as I used to enjoy placing photos in albums within months / years - I dislike the rolling thousands I now have, despite splitting events, etc.

My biggest problem however, is that I obviously don't understand the system.

In early 2013, my original macbook went into meltdown and literally just won't turn on ... I am reluctant to throw as I have ten years worth of unbacked photos on there. Crucial photos as I then lost my eldest daughter. Anyway, that particular macbook is sat aside and I'm still struggling to know what to do with it - don't care for the macbook, just the photos that I stupidly didn't have backed up (in ignorance and age, I just didn't realise)!

I rectified my immediate problem by purchasing an iMac desktop which is now also whirling and slow and freezing. It has huge memory and space so I'm not sure if the issues are the same ... something like 1TB of something and fast on the whatever else (sorry to be vague, but I needed this to be right so stressed the storage / processor issue at time of purchase). It still works, but slow and sometimes freezes completely and goes a little crazy, inventing it's own screens and commands!

Just over a year ago, I bit the bullet and bought a macbook pro retina display ... but again, it is now showing signs of going a little off track.

Totally accept that the fault is with the user, but i just don't understand what to change.

I was accustomed to storing lots of photos in year, then month, then event files on my PC. They are just a rolling mess on iPhoto and I can't seem to turn it off. They appear all over - my iPhone, my iPad, my desktop ... it drives me crazy.

My messages sometimes come to my phone, sometimes to my iPad ... sometimes people say they haven't got one from me at all, even thought I can see it as 'delivered'.

Storage wise, I subscribe to some iCloud thing - purely because it keeps telling me that my storage needs renewing, but I haven't a clue what is stored where or how to control any of it. I do back up my current macbook to an external drive, so I'm not sure what is where.

I've tried to back up iPhoto only but it has two iPhoto libraries which confuses me more and I have no idea how to tell which is which. One is empty and one is the real McCoy - no idea why there is two?!

I've done the extra cover thing and attended a couple of sessions, but my closest Apple store is 2 hours away and, with the booking restrictions, I seldom get more than a mixed group session and a quick one to one which sets me off but then ???

Iphone 6 is my least favourite phone ever and I haven't committed to replacing my iPad ... all in all, an i-mess and am just about to jack it all in and return to PC thinking, although I do like some aspects of Apple. Would love to figure it all out, but is it as complicated as it appears?

Any suggestions (other than theobvious to chuck the lot) will be gratefully received.