Both Norton Internet Security and 360 provide the same level of protection against malware, and I'm saying this because the 360 suite is, basically the Internet Security Suite + some PC Tuneup features + a Backup module.
Here is a comparison table of this two versions : http://us.norton.com/comparison/promo
My personal advice would be to go with Norton Internet Security because this product is cheaper and you can always add some others (free or paid) third party programs that can help you with PC Tuneup and Backup.
Another good reason why you should go with Norton Internet Security instead of the 360 version ,is the fact that Symantec always releases more quickly the Internet Security versions.