I have had similar issues twice. The first time, it was with an Acer (vista) laptop that was still within warranty period.The frequency of connection dropping steadily increased to once every two minutes or so. Acer tech support was useless. They walked me through the stuff I had already done. They tried to blame my router, verizon'ls lines and everything in the world. My other laptop worked fine during that time. Finally, they acknowledged there was a problem and wanted me to send it back to them for service. I installed a driver that wasn't "meant" for my model and the problem went away.
The second time, about two months ago, my net book would connect with the router but with no internet access. I updated the realtek wifi driver to no avail. I had to start using a USB wifi stick.
To go back to the question posed in the OP, I don't see that a wifi adapter can cause a hardware failure in the router. The problem has got to be software based. Come to think of it, my latter problem might have occured after Windows XP SP3. I had turned off Windows updates for quite some time. My problem occurred after I had turned on Windows updates. When was Windows XP SP3 released?