thanks dear
can you please comment on following two:

4) I want my GUI thread to be active always (and worker threads to work independently). How to achieve this?
***Just don't block the GUI thread. You can use custom events to comminicate with other threads***

How to achieve this?

And

I m planning to use QT3.3.4. Is that OK or should I use QT 4.1??

I mean all these questions can be very trival to you but confusing for a newcomer for me...

Thanks...