UP&P (Universal Plug & Play) allows your computer to connect to other computers, for example in a shared network, and allows you to use other network based services. However, due to some exploits (such as buffer overrun) you can disable this service which can solve some related freezing problems. Remember that, most importantly, you will not be able ICS (Internet Connection Sharing) once this is disabled.
To disable this service you need to get to "My Computer" in the "Start" menu (or any other way) and right-click on it for the drop-down menu to appear. Select the "Manage" option. Double click on "Services and Applications" and then "Services."
Find the "SSDP Discovery Service" in the services list and click on it. On the toolbar above select "Action" and click on "Stop." You can also right-click on the SSDP and select "Stop" from this menu.
You can also check the following Knowledgebase article:
Turning off SSDP services