1997 Chevy Blazer 97 Blazer doin' some crazy things!

Hello,
A couple of weeks ago I asked a question about the 97 blazer I own. The problem was it was not starting and none of the dash lights were coming on. When the dash lights did come on, it would start just fine, problem was they never came on. Was suggest-ed that it was probabaly a bad ignition switch. O.K. Here is where I'm at. Went out the other day a got messin' around a little with and got it so now the dash lights pop on about 75% of the time and it starts up but vehicle is doin' sme funky stuff. Half the time the headlights that come on all the time when ur driving in the day and so on, safety lights I guess? They are only coming on half the time, speakers are in and out when playing radio or cd player, one time when the dash lights did'nt come on I tapped on the fuse block and then they popped on? Whats is up here, how do u know where to start? Is it in the fuse block, is it ignition, a bad ground somewhere? Something loose? What. Any help appreciated.

Thanks,
Glenn