Torrent Problem

ok.
i have some torrents on my computer but i'm not able to extract the files from the torrents. Everytime i try to my computer either crashes or i loose internet. I read that it's because i get internet through a wirless router. Has anyone else had this problem or does anyone know how to fix it. Ive tried many different torrent programs including :
Bittorrent
Utorrent
Ktorrent
azureus
and a few more.

Thanks