I use VideoPad for several years, occasionally.
It is free, in French, very intuitive.
The free version does not export to mp4 but just export to AVI (with MPEG4 codec) and go through a converter (eg XMEDIARECODE I recommend) for MP4.
The value for money is pretty unbeatable because the price is zero.
For more technical needs, I use Edius.
Also note the very good tool for audio files the same édietur WavePad NCH.