Don't worry.
Have a go at updating the driver first. Go to Device Manager and right click the router and choose Update Driver. When going through the Wizard, on the first screen, don't let Windows Update search for driver, choose the last option "No not this time"
On second screen choose the 2nd option to install from a specific location (rather than let Windows search for it automatically). On the next screen you should have a "Have Disk..." button. Point it to the drivers you downloaded earlier and it should pick them up. Make sure you unzipped the files you got from the internet before doing this though.
Don't worry if it complains about the drivers not having passed Windows testing, just click "Continue anyway...."
I'm hoping what I described above is correct as its from memory. It might differ slightly.
If you get really stuck it might be best to do a System Restore back to a point before you installed it the first time. Then try the install from CD again. I'm hoping you're familiar with System Restore. Let me know otherwise mate, happy to walk you through. :Cheers:
Edit: forgot to say, it's always best to install the software first before inserting the hardware. Easy to say now though!!