One thing to try on the PSN there was something called the metal gear database, in it contains every character, storyline, weapon infact EVERTHING related to Metal Gear. One huge benefit of this is that spoilers are blacked out until you have done that part of the game in MGS4. So say for example you dindt know who big boss was or Zanzibar land the MGS database will tell you but not give any spoilers away until you have finished that story arc in the MGS4, best of all its FREE!
As for the game itself, dont be put off with the talk of long cut scenes, skip if you want ( i wouldnt though), its an amazing experience gameplay wise. Its one of my Favourite games of all time, and possilbe the best this gen (until i play U2 lol). Keep with it and you will have great fun with the game, if it gets a bit heavy stop playing for a while and come back later.