I dont know for Opera but Firefox does not have a "Download Manager". It is called download manager but the only thing it can do is cancel and resume an ACTIVE connection. if you close the browser, the download stops and it cannot be resumed, you have to start from the begining.

U can download an extesion called Downloadwith...it allows to pick a download manager that is installed on your pc when you try to save a file from the net.
DAP has a lot of spyware as samer said..
I used to have Mass Downloader, but it expired.. now I'm using FireFox
I also downloaded Sun Download Manager, but it didnt work :s lol
try Flashget, I have never had a problem using it. and you can also download an extention for firefox (it's very small 30K I think.)

dmextension.mozdev.org

cheers.
3 months later
thanks for the link Dark_angel
btw, welcome to lebgeeks - enjoy your stay :)
Thanks Samer.

nice Forum btw, Keep up the good work!
i used to work with getright but after the last format i installed dap but i think i am going to revert to getright
DAP is what a download accelerator should be .... of course without the annoying parts .....
sam is right you should try Flashget it's soo fast
my cable is really slow but with Flashget the download speed can reach 20 kb/s