You marked a heap of posts as solutions. Doesn't close the thread. Only the mods can do that.

I've never taken any notice, but some of the red ones are 'hot' topics, whilst others are 'hot' topics the I (or you in one) have replied to. I have no idea of what defines hot. Probably the number of posts over an arbitrary period of time.

I'm set for newest first, automatically go to last read. Or something like that. If you go into 'My Settings', up the top when you're on the boards you get about a thousand options.