virtualbox.org

i have virtual box 4.1.18 , i have for my pc a network wireless, but i see thath virtual box network lan is always active, does it slow down my pc on startup? how could I do that is active only when the program work?

Do you mean the Virtual Host-Only Ethernet Adapter? I've never noticed that it slows down my PC. I would not recommend disabling it.

yes but it is always active!

Moving this topic to "Windows Hosts".

Always active? I don't see how. It's job is to send and receive ethernet packets. If nobody is sending it anything (impossible if no VMs are running), and nothing is asking it to send anything, then it should be idle. I suspect that your Vita host might be probing that network connection to see if its an open security risk. I think there's an registry setting to tell Vista to lay off, though don't ask me what it is: I'm not a Vista user. Google would be your friend there.

i have win xp sp2 , i click lower right on network wireless icon adn appear the virtual box only host network : connected but i don't have open vbox.it is normal?

Your profile says that your host OS is "MS Windows Vista".

Yes, it is normal for the host only network to show as connected. Displaying that connection in the taskbar is an optional feature of your host OS, which doesn't consider this network device as unusual. I usually turn off the network taskbar icon for this device since it isn't telling me anything I need to know.