Welcome to the forum, Zelbinian.
Those are some laudable and, in some cases, ambitious goals you've set for yourself. They are all achievable, more or less. The best place to start is with your first bullet, which is the easiest one to accomplish, and will add to your general level of confidence and competence. Your second bullet is probably the most difficult to achieve, depending largely on your definition of "harmonious", but working on several of the remaining bullets will help get you there.
The only thing you really need to decide before you start is which distro(s) you want to install. Given your broad list of objectives, you'll probably want more than one. A distro well suited to running media servers or MythTV might not be the best one for hosting your personal website, a DIY NAS system, or running the various mundane workhorse local servers you'll need to satisfy your harmonious working co-existence goal. Even so, I'd suggest minimizing the number of different distros you have to learn and support in order to maximize the ease and speed of installation and to be able to share customizations between systems.
To get started with obtaining help on this forum, just pick a topic or task you're interested in, and post a question about it. Open a new thread for each unique question or topic. Always specify the distro you're using and give as much detail as possible about any problem you encounter, and explain what you've done so far to attempt to resolve it. Keeping each thread narrowly focused on a single issue or question generally nets the most useful responses.
Welcome to the party, and good luck.