This is for all to consider! Many use Obs and fraps. A few use bandicam. Which one is better for recording gaming videos? Obs,Fraps,or Bandicam.....
It really depends on what you want to do.
OBS is great because it is free. You have a lot of options that you can tweak (bit rate, encoder, etc.) like most do, but it also allows you to do quick and easy set ups, such as setting quality as "Indistinguishable" for instance presets a lot of things for you. Downside to OBS, it does not handle dual audio very well. Yes there are ways to set it up in OBS that it will do it, such as using virtual audio cables, and saving it as a MKV file. Personally right now I use OBS and I use Audacity to record my audio separately. I have a few tricks I do for syncing audio and that seems to work pretty well for me so far. It can be tedious, but I do not like recording all audio on one track to edit. Makes it hard to tone down when I get jump scared in game.
I know Bandicam is nice, has a lot of the same features of OBS does, handles dual channel audio pretty well as well (records as two separate tracks). Downside is, you have to pay for it.
TLDR version. Just get whichever you want to learn and use. Personally I like free, but take a look at more in depth comparisons of OBS/Bandicam to see which you prefer. Personally I had horrible experiences with FRAPS. so I tend to avoid it.