You should choose between avast and bitdefender. In my opinion avast is good enough. Then install something like malwarebytes or hitman pro and run a full scan. Then install an optimize software like advanced system care and run full optimize. Tell me if it's working
For Old Laptop i recommend remove Bitdefender and Avast and install only Webroot SecureAnywhere with license 6 month by MalwareTips and CCleaner of Piriform for maintenance all pc for smoothy running.
Don´t forget instal a defrag program like Auslogics disk defrag free or smartdefrag 3 of IOBIT and a backup/restore of your system.
You will see better and high speed.
My personal opinion is to never use two real time scanners, it will drastically slow down your computer and could cause errors and eventually kill each other. What are your hardware components?
Have to agree with everyone else, with an older 32 bit system, i would personally drop Bitdefender, and either run Avast, or find a like minded/light AV.