Is there anyway to set the default connection to either nothing or wifi?

current if I am looking at Settings >> Connections >> Advanced and "Select Networks. the default is Sprint.

If I try to create a new connection "select a modem" only give me celluar line, bluetooth, Generic IrDA and COM1 no wifi.

it's even better if I can disable the phone from browsing internet using sprint's network. of course only my phone have access to Evdo