I hate to do this to you 53defense but here is a detailed explanation of WRC and WRC+
Weighted Runs Created (wRC) is an improved version of Bill James’ Runs Created (RC) statistic, which attempted to quantify a player’s total offensive value and measure it by runs. In Runs Created…
library.fangraphs.com
If you understand WRC (weighted runs created) then WRC+ merely takes into account the effect the field/league has on the WRC results. For example someone hitting in Coors field will have a much higher WRC than someone at San Diego. WRC+ takes that into account.
Since it takes into account field location, I don't think its that useful for fantasy drafts. Fantasy leagues don't care where the game is played, they just care about positive stats generated.