So basically, I'm a shit show! I'm 20-25 lbs overweight because my diet is crap...I mean I eat unhealthy choices, not crap). Fixing my diet is "easy". I know what to do and it boils down to me doing it. The difficult part is working out.
I have a bad lower back. The discs in between my vertebrae are fucked. A few years back, I did get shots to help with the pain and made it manageable in everyday life but makes it very difficult to workout. I also think I have this in my upper back/lower neck, but never had an MRI yet. Add to that I have bad knees, angles, and shoulders from doing things "i'll regret when older". Needless to say, my 41 year old body feels like a 71 old body. When I do workout, I hurt for days afterwards (yes I understand the difference between hurt and sore)
Being my body is shit, what are some options to get healthy? I'm getting a physical on Monday, so am going to visit with him a little. Any other suggestions how to get my body in a position that I can workout?
Swim? 
If there is one thing even you admit that you can do but just aren't (diet) then what makes you think you'll have the discipline to work out too?
What exactly is holding you back from changing your diet?
trt. wholistic doctors
working out is the easy part for me, well it was. I've always struggled with eating well.
But you are right, I HAVE to my diet in line. Working on that!
I have back problems, and I've let it be an excuse not to work out and gained weight a couple times over the years.
Here's what works get serious about your diet & start walking. It'll get you moving again and bump your metabolism while you are giving it good fuel.
When the weight goes, your back will start feeling a ton better.
Diet means healthy shit more than it means starving yourself. Start with light cardio and build up from there. 
- Get your back fixed.
2. Do physical therapy for the other things.
can you bike? If not, you could always get one of those reclining bikes. You can walk, so take some long hikes. You can probably swim too.