To optimize your system and / or your broadband connection, I use
TuneUp Utilities 2004 . You can read my review on it which is in this forum under the name of Optimizer Programs. You can also download a 30 day trial by clicking on the link. As far as download accelerator / manager programs go,
Internet Download Manager seems to be OK although I personally dont use an accerator. Again you can click on the link for a 30 day trial. Neither of these programs are free but I believe you get what you pay for. You can browse through Optimizers and Accerators at
www.download.com if you really want a free program, but be warned that most freebies carry some sort of penalty, usually in the form of spy and adware.
Alan