Hello camholmes
Vodafone cannot charge you for using your own home WiFi connection or for any other WiFi connection.
If you are concerned about accidentally connecting through the network, try putting your phone in offline mode. You could even browse using WiFi without a SIM card, it is a handset feature and not a network feature.
All Blackberry email is push meaning that as soon as an email is received it is pushed to the Blackberry. It is the Blackberry servers that push email to the phone and not the phone pulling them. The blackberry server polls your email account on a regular basis to check for new mail. I believe the default polling interval is 15 minutes but if it finds a new email it will pool again in a shorter time interval. This means it should never be more than 15 minutes from someone sending an email to you receiving it on your phone. Exchange email is different again as it gets pushed to the phone immediately.
Iphones are different - if you have Exchange then push works in the same way. Ordinary POP3 email uses fetch which means the phone polls the email account directly at regular intervals.
If you have a BIS tariff surely you have a data bundle included?
