If you use a good firewall, (not windows firewall - a good one), such as Comodo, and set it on 'Custom' for the firewall, it will pop up a message for every program trying to connect to the internet. Then you'll know which processes/programs are accessing the internet.You will also get the option of allowing or denying that connection, setting the program as trusted or not, and remembering or not the setting.
There are packet sniffing programs, (some free - some not), that can help you, but they tend to be complicated and not so easy to use for most. You can do a search for 'packet sniffing - Freeware packet sniffing, or variations on that to find them.
Just as an aside, you can go to Black Viper's site and use his custom instructions for turning off/setting to manual unneeded services for whichever version of windows you're using. That might help if your micro-freezes are due to excessive resource usage. Either way it can help reduce the load on your CPU and memory.
And YES, get rid of all those useless toolbars and other crap you might have inadvertently installed on your system. If you're anti-malware program isn't finding them, try Spybot, Adaware, or the free Malwarebytes version to scan your system. You might also check any installed software to see if it is automatically connecting online for updates, etc, etc...
Wabb