By non resource hungry, it'll be better if we know how much RAM you've got
KIS tends to be a bit slow on 512 MB RAM systems (sometimes even on 1GB)
For Such PCs, NOD32 is highly recommended
Otherwise KIS FTW!!!

However, I notice that the PC slows down when many heavy Apps are running with KIS in the background (saying this after using Photoshop, Google Sketchup running along with KIS on my friends PC with KIS)
I'm using NOD 32 at the moment and I'm very very happy with it

So, it's your call, with AVs being on the cheaper side these days, you can buy both and see which one works out