Bitrate and the quality of converted video

[zoki]

Hello,
how the bitrate can influence the quality of the video?
I don't see big difference in video quality if I use bitrate 800 Kb/s or 1500 Kb/s, but file is bigger.
I am converting ripped DVD to mp4 with Handbrake, Virtual Dub and freemake Video Converter.
I have limit how big output file should be -1.44GB.
Which settings to apply?
Thank you!

[jagabo]

Higher bitrates deliver higher quality (all else being equal). How much bitrate you need depends on the properties of the video, the codec and settings used -- and you're personal tolerance for artifacts.

file size = bitrate * running time