Well its a bit hard to figure out what settings you need help with. The T2 is a simple machine with just discrim, sensitivity and audio mode to set. There isn't anything else to change from site to site. When setting up the discrim mode I usually set the discrim at 5 and the sensitivity at about 80 or higher if it will go higher without having too much chatter. Then I will put it in either 2+ or BP depending on the site and how I feel that day. The BP slows the response down some so if there is a lot of targets close together I use 2+ or all metal if the field doesn't seem to have much in it I use BP. If it does chatter I will raise up the discrim before lowering the sensitivity cause the machine's designer said that was the way to go. Since you can have separate settings for the all metal mode I crank the sensitivity on that all the way up to 99 and there isn't really much else to set there. Then after I have everything set I do a ground balance and off I go. Then I will switch back and forth from discrim to all metal to check targets and how much chatter I can stand. The T2 is a simple machine to operate and doesn't really have different modes for different places. I guess if you don't want to hear nails and iron you could set the discrimination at 35 or something but I never do that. That is pretty much the way I have been setting up my T2 and then T2SE ever since they came out. Don't really change them from site to site.
The worst noise problem I have is with electric fences but I usually just ask the farmer if I can shut off the fence while I am hunting. The cattle aren't smart enough to figure out its off if you shut it off for a bit so they mostly let me shut them off. But you can sometimes get rid of or reduce interference by changing frequencies - theres 7 of them to choose from and one of them usually at least lowers it some and sometimes gets rid of it. I don't seem to have too much trouble with power lines unless they are buried in a spot I am hunting. I have one field that does have a power line buried in it as the power company wouldn't run it above ground and made the farmer pay to have it buried.
Not sure what other info you are looking for in terms of setting it up, there just isn't much to change on a T2. The other thing I would say is that you shouldn't slow down your swing in trash. The T2 is at its best in terms of separation when you swing fast. You might want to shorten up your swing to concentrate on the area where there are adjacent targets but you will lose separation if you swing slow.
Can't tell much about your finds, I don't see any man made markings on the lead and the other thing looks like a rusted up clamp to me. If I had found them I probably would have just chucked them but that is just going by what I can see in your pictures.