Upgrade NIS 2014 to 2015?

I am currently using Norton Internet Security 2014 that is for 3 PCs. There are 56 days remaining. It has done a good job for me. I started doing some research and it appears that Norton has changed their list of programs. Maybe I am wrong. What would be the correct program to replace or upgrade my current program for next hear?

My environment is: 1) Windows 7 Pro 64-bit, and 2) Windows Vista 32-bit. PC number 3 no longer exists, but used one of my three licenses.

What programs are available? Please give the Item Number, the Description, and the Cost? I usually buy one program for 3 PCs.

Maybe I should renew my 3-license NIS 2014. Is that an option? Will that extend all 3 PCs? I currently do not need the third license, but I would like it for the future.

I also have a technical question regarding PC 1. I want to completely erase the hard drive with the OS, reinstall the same OS with the same serial number and the programs. Will that use an additional license? If it does not use an additional license, the item for 3 PCs would be sufficient. If it does use an additional license, I don't know how many licenses to order.