Hello.
1-if i apply it to new trackers then add my .torrent file to UT, would i get a peer list(first announce) so i can leech?
TRK blocks torrent tracker's domain for your torrent client and it will not be able to download peers list. It's a good option for the trackers with DHT. If tracker has DHT, your torrent client will get peers from it and it will not report any info the tracker.
2-can i get banned if i use ghostleech in IPT and being long time without real seed/leech(no activity)?
IPT has no DHT. It makes "Block Tracker Communications" useless for this tracker.
3-is there any difference between Block Tracker Communications and check both Seeder mode & emulate upload problems?
Block Tracker Communication blocks the tracker's domain, while Seeder mode and Emulate Upload Problems features don't. Seeder mode shows you as a seeder and Emulate Upload Problems doesn't allow your torrent client send reports about uploaded info. You can also set Download decrease to 100% to avoid any download reports.
If you want to download peers list and "don't do anything", you can set Emulate upload Problems + Download decrease 100%. If you set also Seeder mode, then you will be a seeder that don't do anything. It's ok to use such combination from time to time on IPT, but not all the time, because they are removing/baning "useless users".
I'm downloading torrents from IPT with a 43% upload increase and it works great for my internet connection. I have 10 mbps adsl.