Help Confirm My Understanding of Mode

I would find some chords that sound good with the melody you have chosen and not worry about the mode

You are technically correct but this is a very sanitary, unfeeling way to write music. Russell has the right idea.

For most western popular music the motion from tonic => subdominant => dominant and subsequent resolution back to tonic is a heck of a lot more important than the chord(s) that go along with your melody note in some mode or another. If this is what OP is looking for he'd be better served doing research on chord structure, substitutions and voicings rather than  worrying about what mode a song's in.

In fact, the whole notion of modality is better thought of in terms of melody and scales vs. chord progressions. Consider a blues song in C that goes:
C7       F
C7       F       G

When we talk about what key that song is in, we say C or C major. You wouldn't generally say "it's in the key of C mixolydian" because "C mixolydian" isn't a key. It's a scale.

However when I'm jamming with my guitar buddies I might say "here are the changes. Think C mixolydian when you're soloing."

Home chord is the tonic. Seven bridges Road is an example of a song that is not written diatonically - but your analysis of the song is correct. The chord progression is I - bVII - IV. The lowered 7th chord uses a note from C mixolydian. Same thing in "can't you see."

Here's an analysis that applies to SBR. Might skip to the part that talks about lowering the root."

I hear the sound of a topic going clean over my head. I've tried to understand it.  I've read about it in books. I've practiced scales which I'd been told would help me understand them. Now, I'm beyond trying to understand. That's what I like about the guitar. You can learn as much or as little as you want to about theory.

I can't do maths either.

I posted this a while back or at least it seems some time ago.  Funny thing is it was really only at the beginning of the year.  Time Flies....

When I made the original post I was going through the book and videos associated with Fretboard Theory by Desi Serna.  I consulted with him on this and he confirmed that my description is correct when you are starting from scratch in writing a song.  Of course the opposite would be true on an existing song.

I just wanted a very high level understanding of what Mode is and how it interacts with Chords, Keys, and Melodies. 

I come from a strong engineering background and the learning methods for us left brainers are significantly different then most really good musicians who are "traditionally" right brainers, although there are always exceptions to the rule.  Those of us who view the world from the left side of the brain need to see the whole picture and how everything fits within that whole.  Right brainers approach things very differently...   Again, I am not saying anything about those who have right brain views.  But if you read the thread, you can see there are a variety of views about how to go about this subject.  Again, I am not saying anything is wrong with that. 

This is just how I need my left brain centered mind to go about understanding how Modes fit into the entire picture.

thanks...  I will check it out Jerome.oneil