Question about connections

Hi everyone. I'm definitely a newbie, but so far loving my 8220 flip. I've only had it a couple of days.

In the manage connection, I was wondering what setting I should have it on and how it affects how my blackberry works.

I have a Wi-fi set up at home and a data plan with my carrier for of 500MB.

Should I have both Mobile Network and Wi-Fi checked in the connections list?

If Wi-Fi is checked off, does it default to the Mobile Network or Wi-Fi when I'm at home (or within any Wi-fi area)? Do I have to set up Wi-Fi before Wi-Fi works with my phone? Thanks.

I believe what you want to do is establish a WiFi connection and then select WiFi prefered.