I need phone's file manager and PC connection software to connect my laptop/PC to internet. Is it possible using blackberry ?
Not sure, don't own a BB, but could be tricky.
Android 2.2 does that, and WiFi tethering, out of the box though, so...
I'm not sure android phones are good for PC-internet use, most of the Samsung models are touchscreen, so.. :/
I'm using a Motorola Milestone (the Euro/GSM-version of the Droid) that has a real keyboard. It's also very usable as a touch-phone (without sliding it open). The internet speed is only depending on your 3G speed at that location. (But I'm still on Android 2.1, so no WiFi tethering yet)
Afaik the Droid2/Milestone2 has an even better keyboard (less 'tiles' layout, more 'brick wall' key placement), and the HTC Desire Z also has a real keyboard. There are also some LG models with actual keyboards, but I'm not too enthusiastic about LG phones