How can I copy a file into micro SD of an Android phone connected via USB to a PC with Windows?
should be set to "Disk drive" (you can set this as a default connection type, but I prefer to do it manually when I need it).
Also, you can set it via the notifcations bar by clicking on the USB connection type as it appears; a selection box of the various options should appear.
Once mounted, you can open on your PC, and drag-n-drop, or what-have-you.
NOTE (from the Incredible manual, p29):
You don't mention which Android phone you've got, depending on which phone (and how much your manufacturer's customised) you've got, it may be slightly different from OtherMichael's instructions.
With stock Android (as on the Nexus One, HTC Magic, G1, etc), when you plug your phone into the PC's USB you should see a USB icon appear in the notification area. Pull the notification area down and you should see "
Other manufacturers customize things slightly with their custom UIs, for instance if you have a phone with Samsung's TouchWiz UI on it, you get a menu up as soon as you plug into USB, with options to select USB Mode, on the you'd pick Mass Storage, and then do as above. I think HTC's Sense UI also customizes things slightly, but I can't remember exactly how that works.