I'd forget about download managers right now if I was you. I'd be more worried about my flaky internet connection.
Disconnected every 5 minutes is quite severe. I am not sure how or why you would even put up with that.
There must be a solution that can fix this assuming that you are connecting to your wireless router and not stealing a neighbors.
Perhaps if you could tell us about your PC, router, location of PC compared to router, etc we could help you fix that, then a download manager would be virtually useless.
