You do not have to re-install bit torrent unless you have registry problems I.e you use registry cleaners.
You should only need to use one port.
For example lets say you make Your port 5800-5900-5700; this port will not work because it uses a different program (vnc)
My advise is to go here: http://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers
and choose a port that is not listed in the list and use it for bittorrent or whatever program you are using i.e bitcomet etc... put the number in the settings in the program i.e preferences. Than go to your router and put in the port number you selected.
If you have any other questions regarding this, or if it doesn't make any sense feel free to give me an email at:
[email protected]