8GB RAM could be one issue. The game usually uses 1-2GB, depending on how long it has been open for, but it uses the RAM kind of inefficiently, or so I have noticed. If overall RAM usage is at 70+%, things get sluggish. So try and close any other programs that occupy GBs of RAM. Browsers are culprits there, but also stuff like Discord, if you use the software. You can sort programs by RAM usage in the task manager.

Performance issues specifically in the menu point to your hard drive. DbD (nowadays) writes after basically every single click in the menu. You should definitely look to get an SSD. For the time being, make sure your HDD runs in AHCI mode, is not too full, nor too fragmented (you should have around 50-100GB free, and you can use Windows' own defrag utility). You can also use software to check the disk's health, and use Windows tools to try and repair file system errors and such (chkdsk).

As for performance tweaks, I will forgo mentioning any hardware and OS stuff since other games seem to be performing fine. You should run the game in true fullscreen mode, and from there you could reduce the actual resolution if you want more FPS (though 60 is fine for this game, if it's stable). Setting the game to low quality helps too, and it's not like the game is particularly eye-candy otherwise anyway. There are some additional variables I can also give you, primarily to disable Anti-Aliasing which makes the game awfully blurry in low quality mode. This is all done through config files, so let me know if you need help with that.