I have astro file manager, and the bluetooth module installed in the phone..but,i still dun seem to see the effectiveness of transfering files thru this app..can anyone suggest a suitable, convenient, bluetooth transfer app for android? tq

You need "Bluetooth File Transfer" app.
Android doesn't build-in the FTP & OBEX Transfer protocol on its system.

That's why Android phone can't transfer file with Bluetooth.
Once you installed it, all bluetooth transfer shouldn't be a problem.

how about turning on bluetooth and connect to the computer so that the phone can work as a modem for the computer to connect to the internet?
Can android phones do that?

Nope. Only work in Froyo but that feature uses WiFi instead of Bluetooth. It is called Wireless Tethering.

Meaning that if my place got no wifi, I can't connect using bluetooth via my phone?

So sad. Better stick with my symbian phone for now.

For me, I prefer Wireless coz all devices even the PS3 can use it although limited to 2 devices connected simultaneously.

Yup.

Samsung galaxy S can.. Connect ur phone to computer.. N ur phone able to become as a modem..

For WiFi Tethering, you can use this on a rooted Android 2.1.
http://code.google.com/p/android-wifi-tether/
Of course not all Android are able to do so. Refer the model list on the web page.

BTW, you also can use "Barnacle Wifi Tether", search on the Market.
(There are other Wifi Tether apps too that I have never tested.)

You can also google "Wired Tether" on Adroid that can use USB to connect as a Modem. But somehow, have to manually modded the Firmware to support wired tether (I think it means to install the "Modem Driver" protocol or else).