Every time I saw a computer trying to run McAfee it was struggling to do everything. It's worse than Norton. The reason I didn't tell the OP to get away from Norton was because I've read reviews that said the latest version was actually pretty good. Now I stand corrected on that. I guess it's still just as bad as it always was.
I use Eset Smart Security myself. It's so light on resources you never even notice it's running til it tells you about having updated the virus definitions or blocks a virus or it asks if you want to allow a new program to access the internet. It checks for updates once an hour. I've seen it update 5 times in one day before. Every time I didn't know it was happening til it told me it was complete. I've been using it for 3 years now and I swear by it.
It's not free but it's a small price to pay for the peace of mind it gives me.
Operating System Windows 7 Ultimate x64
Computer Type Laptop
CPU Type and Speed Intel Core i5 430m dualcore
Motherboard Chipset Inspiron 1764 Intel HM55 Chipset
System Memory Type 4 GB DDR3-1066 SDRAM
Video Card Type and Speed Intel Graphics Media Accelerator HD HDMI
Computer Monitor 17.3" HD Laptop monitor
Hard Drive 3B29 WDC WD5000BEVT-75ZAT0 ATA 465 GB IDE
Optical Drives Optiarc DVD+-RW AD-7585H ATA
Network Adapter Realtek PCIe FE Family Network Controller + Dell 1520 Wireless-N Mini-Card
Anti-virus Software ESET Smart Security v4
Computer Skill Level Self-Taught Expert