1) This is not urgent. You putting that in a thread title when it isn't just pisses people off. People here are not at your beck & call; this isn't your personal tech support hotline.
2) Your thread title is misleading/dishonest (just like the 'urgent' thing). You don't have an S2 with busted WiFi as the title suggests, you're looking at buying a phone that has busted WiFi. It's not the same thing.
3) If you buy a 2-3 yr old phone with busted WiFi at any price other than free, that makes you a (dishonest, as we've already established) fool.
If it's important enough to cause you grief if it's lost, back it up. No excuses
Trolling for thanks is lame
Does Samsung's auto-brightness implementation crap drive you to self-harm ? A solution !
Failure to search is the leading cause of male impotence on XDA
If you don't know how to recover if things go wrong, what are you doing flashing custom roms ?