Kaspersky is pretty well-known as being one of the most processor hungry antivirus suits out there, so you'll probably notice an improvement with almost any other choice.
For Paid options:
I've been using Bitdefender for the past year and a half and it's been great. Not sure what exactly you need in terms of features like parental controls, but it has several options that should suit your needs. http/www.bitdefender.com/solutions/internet-security.html
I'd also recommend looking at EsEt. They are another very well reviewed company that makes premium antivirus. A little more expensive, but equally awesome. **Note: I have seen reviews that commented on this being a bit of a resource hog as well** https
I'd go with something like Avira. Nothing fancy, just a good anti-virus that isn't as invasive or annoying as Avast or AVG has become. https