Safe, reliable download manager?

Ages ago when I was a kid, I used to use flashget, but as far as I'm aware it's become a spyware/malware riddled mess.

My primary reason for wanting to get a download manager is because I really hate it when my downloads reach a good percentage completed, only for something to happen like the internet zonking out, or perhaps windows decides NOW is a perfect time to install updates and restart my PC, causing me to have to restart my download from scratch, that in itself being a problem if the download speed from the that particular site is lousy. Currently downloading some hefty files and the download speeds are terrible.

I'd love a free download manager that won't riddle my PC with spyware, malware or obligatory third party content. Any suggestions?

Firefox has informed me that some of my downloads have failed, but when I hit retry....I THINK they resumed from where they stopped? If one is available though, I'd love a download manager, even if only temporarily.