Does anyone have any really good software for converting youtube videos to an Ipod Classic?

I used to have a great software for converting you-tube videos which I watch on my Ipod Classic. However, just recently it seemed to stop working for some reason, the software was DVDvideosoft. I would love some suggestions for an alternate program for pulling videos off you-tube, preferably one not hard to use and one that won’t put a gigantic virus on my computer. Any help would be great, I feel lost without the ability to put videos on my ipod anymore :(