Learning about wine, and when to drink?

Im currently learning about wine. I have a book that goes from everything about making it, the grapes from different regions, tasting, studying the bottle and pairings but im still confused about some things. It offers a sort of grid for an example wine of when its at its peak, like in 10 years. But how do you know which wines are able to age and which are not and when its ready to drink. Its not like the bottle says drink in 5 years. I have a bottle - Clover Hill Vineyards & Winery Concord- that's really sweet red and served chilled and the bottle says consume within 1 year. But then I picked up a bottle of Sutter Home Sweet Red California Sweet Red wine 2009 This is the first bottle i've bought that has a year on it, does that mean its already been bottle aged for awhile and should be drunk right away. will it be bad if i wait till the end of summer? and for when i buy bottles later that have different years how do i know when to lay them down and when to drink them. Please help I really want to learn about wine.