Can't connect to ONE Internet Network after Reinstalling

Today I decided that I wanted to change from Windows 7 32-bit to 64-bit, so I backed up everything on my Windows partition and reinstalled Windows 64 bit the same way I did multiple times before (except with 32 bit). Everything is set, and Windows is working, except for the fact that I can't connect to my HOME network. I did insert the OS X DVD and install the drivers, and I know they are there because I can connect to other networks that aren't password protected and access the internet fine (albeit slowly). As well, other computers in the house can access my home network just fine. But when I reinstalled Windows 7, it recognizes the network is there and shows the highest connection (five bars), but when I try to connect to the network and input the password correctly, it tries for a while but fails to connect every time. I don't know what the issue is, but it's solely between my computer and this network - no other computer, including this one, has a problem with it, and my computer can connect to other networks normally.

What I have tried is:

• Reinstalling/Repairing the drivers. Did not work.
• Reinstalling Windows 7 64 bit AGAIN. Didn't work.
• Restarting the computer, trying multiple times and downloading Windows updates - none worked.

I tried troubleshooting, and the advice given was to restart the network. The problem is that I'm leaving in a few days (which is why it's not that big of a deal), but if I mess up the network by doing something wrong, my dad is afraid the internet could go down and we won't know how to fix it (we've had troubles in the past, and now that it's working we are both afraid of ruining anything).

Does anyone have any advice? I'm going to college in two days, so it's not that big, but knowing if I could fix it to download a few things before I head off would be cool.

Update

UPDATE: I tried resetting my router today while my dad is gone, no dice. The router works on my other computers like this one, and my computer connects to other networks normally, but this router seems to just not want to connect with my computer. Before I reinstalled Windows 7, it was working fine for years.