need help transfering DVD's to hard drive (Los Angeles)

Not the most technologically or computer savvy person.
I understand a decent amount but tend to get easily flustered when faced with something I don't understand or can't figure out, which this happens to be one of those cases.
I have tried a few different programs in order to convert and transfer the mp4 file to a hard drive and every time to movie doesn't come out right.
Tried a few different movies and a few different settings to no avail.
Any help or assistance would be greatly appreciated.
Working with free programs as I don't have much money and I have a HDD hard drive if that matters at all.
Like usual, probably missing something obvious but just can't figure it out.
Any help would be appreciated.