Stopping Wireless Card Connecting to open hotspots

This laptop keeps connecting to someone elses wireless router which
apparently has no security running on it. This obviously opens my
laptop up to all sorts of risks.

My question is, is there anyway to stop my laptop using this open
access point? I'm using KCORP's own software to configure my laptops
wireless card, but there doesn't seem to be any way to stop it from
using this other open hotspot. I've only setup one profile in KCORPS
software for my own wireless router, but this doesn't help, and worse
it frequently loses my own networks password... Which might be the
reason it connects to this foreign router.

Can anyone offer any advice? Or are there any third party tools I can
use to manage wireless networks?

TIA

CS