There is two ways to connect your Android phone and depending what you want to do you need to choose right connection type.
To browse your Android photos, music and videos connect your device in mass storage mode.
HTC, Google and Samsung – When phone is connected to computer via USB cable, USB icon appears in the status bar. Drop-down status menu and you should see "USB connected" notification. Click notification and you get confirmation box where you can select "Mount" or "Don't mount", select "Mount" to browse phones media.
Motorola –When phone is connected to computer via USB cable, USB icon appears in the status bar. Drop-down status menu and you should see "USB connected" notification. Click notification and you get list of different connection modes, select 'Memory Card management' mode. Media browsing wont work in 'Motorola phone tools' or 'No usb connection' modes. If you select 'Windows media' your phone shows your phone media little bit differently and you may not see all of your media so this is not prefered mode.
Other vendors – If you have some other vendors Android connecting your phone should go in similar way.
To browse your Android applications you need to enable phone debug mode and install ADB drivers. Enabling debug mode in your Android go; Settings -> Applications -> Development -> and check checkbox 'USB debuging'.
HTC – After installing 'HTC sync' connect your phone via USB cable and you will see USB icon in the status bar. Drop-down status menu and you should see "HTC sync" notification, click notification and you can start browsing your applications in dazzboard.
Motorola – After installing drivers from Motorola Media Link cd. You should be able to browse your applications in dazzboard in any connection mode, remember to enable debug. (Note: to get best usage experience enable debug and use your device in Memory Card management mode, then you can browse your applications and media without changing modes.)
Samsung – When