[koohead]

So working with many Frenchmen who I have been trying to explain baseball to for 12 years now, I appreciate your interest and desire to learn the game and sport.
Let me zero in on something you mentioned as a reason why you are exploring OOTP and baseball to start with...the data. Baseball does offer up volumes and volumes of data and one could easily spend hours a day just looking at the data. So that would be what I would offer as far as where to start. Take over a team, does not matter which and whether or not it is a real world MLB setup or a 100% fictional league. Just pick a league and team and take it over. Now...to save you some headaches for the first 2-3 seasons, go to your Manager options and assign ALL responsibilties to your bench coach or assistant GM. This essentially allows you to watch the game/team for as long as you wish, but still feel as if you a stake in the game because you are monitoring a specific team. Sim a month at a time, taking time at the end of each month to look through your league, your organization, and your team. Spend time looking through the players up and down your org and see how their stats are. Your first goal is obviously your team record...hopefully you can maintain a winning record but if not, you can decide what direction you want to take the team in seasons 2, 3, and 4. Are you going for the championship or is it time to tear things down and look towards the future (year 5+)? After the team record (and the records of your teams in the minor leagues), you can start following a few select players. Start with who the game suggests as your Top Players and top Prospects. that'll give you 6 players out of 1500 to keep an eye on and get to know. Watch their statistics closely to see how they are performing. Are the "top players" performing as cornerstones of your franchise or are they barely delivering value? Are your prospects developing and making progress up the organization? Or are they stalled and won't turn into MLB players and will be career minor leaguers?
Do this for 2 maybe even 3 seasons. Focus on the data. look at every leaderboard and report the game has to offer. Look to websites such as baseball reference.com to learn about the various statistics that the game tracks and reports on to understand what exactly you are looking at. If you do this for a few seasons, just getting yourself familiar with the data and with a few players, the game starts meaning something to you beyond the wins and losses.
Then start taking on more and more responsibilities. leave your bench coach to manage the day to day and just focus on the draft for a year or two. Or maybe just work on signing free agents for a couple seasons. maybe take over moving people up and down your minors. Whatever you do, take on a small number of tasks each year and build up to the point where you are running the org. This might be year 10 or more in the whole scheme of things but by then you will know names and have built up a little "investment" in that team and will take every losing season personally.