Switching Norton Programs

Hi, I recently bought a PC that came preinstalled with 2 months of Norton Internet Security (NIS). When I bought my laptop, I also purchased a box copy of Norton Antivirus (NA), not knowing  NIS was preinstalled. I'm wondering what route is best to switch from one program to the other after the 2 months, since the NIS won't recognize the NA product key, being that they are different products. Should I just uninstall NIS, and install NA at the end of the period? I think it'd be better to have one always active, but I don't really think anything bad will happen in that short period of time.

 

Thanks,

Ben