Trs Cables? Options

[musico2007]

should i use TRS cables or just regular 1/4 inch cables for my monitor speakers? I asked the guy at GuitarCenter what was the difference and he told me they were shielded and that they're better but that's it...he didn't really explain to me and i'm not experienced with the cables in this nature. I just wanna know what would be the difference between the 2 cables and if they would really make a difference. At the moment, i sometimes get some radio interference from my speakers and i bought one TRS cable to see if there would be any difference but i really don't see a difference. I only get interference "sometimes" and other times i hear nothing. If anybody could help me with this i would really appreciate it, THX.