Sorry to say, but this is almost certainly your fault. While I'll certainly agree that I'm not a fan of the practice companies have of bundling some kind of toolbar or other program along with anything else you download or making the default option opt-in, ultimately YOU were the one who wasn't paying attention and just kept clicking "Next" without reading each screen. Meaning you had the opportunity to avoid installing this sweetpacks program, but were in such a rush to install whatever you downloaded, you didn't notice the extra screen on the installer asking if you wanted to also install this other program.
As for removing it. Spybot and Norton rank pretty much at the bottom when it comes to removing malware, so give something like Malwarebytes a try.
I have tried twice now in the last week to download a dvd playing system off of download.com, a cnet service provider. The first time I downloaded the real player software and got a virus/adware called sweetpacks and was unable to remove it with both spy-bot and norton antivirus so to solve the problem I used a system restore point from a week earlier and started the whole process over. The second time I downloaded the top rated player and once again the virus/adware called sweetpacks was installed onto my computer. If this is something that you include with the downloads from your website then I will no longer be using this website and I believe that nobody should because it is obviously wrong of you to install this on my computer without my knowledge. Please let me know if there is any way that I can remove sweetpacks without once again having to do a system restore and if this is part of your downloads then please let me know so that I can chose to go somewhere else for more reliable downloads from now on.