For the second floor telephone you might consider a wireless basestation phone that would in turn communicate with the remote phones sets located anywhere in the house where there is a power outlet. Then that would do away with the need for the "Second floor" to "Ground Floor" wall jack to wall jack connection.
You appear to have the physical connectivity but it is still very cumbersome and round-about.
That said, probably need to reconsider your options. Details matter.
Are those wall jacks already in place or are you planning to install them? Are the existing jacks in parallel within each room or individually served by their own wire? Could be a combination of individual or branching.
I think it would be best if you have a telephone line junction box (or patch panel) at at the point where the line from the service provider enters your house. The junction box would provide a one to one direct connection to one wall jack within a room. Then other wall jacks within the room may be run in parallle thereafter.
You may already have a junction box or something similar. Google for images:
E.g.:
https://www.google.com/search?q=telephone+patch+panel+diagram&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwiWj-PPvLzQAhUE9GMKHWiNBnQQsAQIHA&biw=1293&bih=723#imgrc=oBN_ZXCQVOb6AM%3A
No problem with being a noob. Always things to be learned.
What I suggest is that you go online and look for tutorials about installing junction boxes, telephone lines, wall jacks, etc. That way you can read and research what is most applicable to your situation. Especially junction box connections.
Key is to do what you have done. Diagram it all but start with all of the existing connections and wall jacks. Then work on what you may need to add.
And, which I should probably have emphasized more, do take a closer look at all existing wall jacks. Especially if dual ports. One port could be ethernet (RJ45) and the other port telephone (RJ11). That will make a big difference in the options available. If you have any central connection points look for labels identifying where the cables go. Hopefully the installer did that and left the information somewhere. Also look at the wires. Not uncommon for some installers to use whatevery wire happens to be available.... as long as there are four or eight conductors available within.
Very much worth taking your time and planning things out. Post your plans - may need revision but that is often the case. Someone else may spot an error on my part or suggest other options. No problem with that on my end.
If you do end up needing to run more connections and installing wall jacks then the project becomes bigger very quickly.