SK @AkosBakos mentioned is your best reference mate. But, having said that, I would NOT modify those settings you mentioned in global properties. I once had customer call me in panic saying, ra is broken, vpn tunnels are broken, I call her, find out she changed bunch of those settings because she read online they can help. Well, needless to say, I told her to revert it and all started working again.
Im sure she had lots of explaining to do with her boss after lol
Anyway, UNLESS there is a good reaosn to change them, I would not bother, just my personal opinion.
Andy