How should returning players deal with the game's changes...

Dear Boards;

I'm a returning player who spent the majority of his time playing on the "old rift" focusing on the middle lane ( M-lane, with the bottom/top lanes being B/T-lanes ). Upon my return I put in $30 and picked up two champions: a former favorite named Viktor and Yorick; who I had always wanted to try but never made time for. I found I didn't like the changes made to Viktor, found Yorick interesting and discovered that the M-lane didn't appeal to me the way it used to. I'm not totally ready to give up the M-lane but have come to the conclusion I want to try playing all of the roles ( Realizing I'll need to wait a while for the new Jungle ) and am wondering how I should go about relearning the game as a returning player.

Unfortunately I don't know enough about the game's current state to ask any specific questions. Ideally I'd like to learn a little bit of general information ( which I am scouring other threads and outside sources like the wikia for ) about everything so that I have a small knowledge base to begin experimenting with. Any advice you can offer on your area of expertise would be appreciated. For those wondering; I've felt most affinity with the top lane thus far but am most curious about the Jungle with a mild interest in seeing how the role of support has changed.

Thankful for any constructive input; Esjaibie, a level 7 unranked summoner.