Yes, the iPhone 3G has Wi Fi.
3G is the service for things like the internet... just like in the old iphone there is Edge.
No. It can use your 3g
You get faster internet then the original iPhone.
iPhone 3g is capable of 3g access, but not iPhone 1st generation. However, some areas do not have 3g coverage, so iPhone will automatically switch to EDGE. iPhone 1st generation only has EDGE and Wifi, and iPhone 3g has EDGE, 3g, and WIFI.
Yes, you can use your iPhone 3G(S) to access the Internet if you have an available WiFi connection.
Connect to either WiFi or 3G and go to Safari. Start searching.
It has always had internet. Edge now 3G or WiFi.
The iPhone 2G does not have the hardware to capture a 3G signal. It does not matter where you are.
Yes
to look tidy
Yes. All iPhones are capable of standard 3G connectivity (on most bands) except for the original iPhone (launched 2007, no longer commercially sold).