Why is a wallet so heavy for CPU? + 40-50% Athlon 2 (am3+) 2cores
It's quite easy to fix if you are running on that slow PC.
Go to Help -> Debug Window -> Console
Type
setgenerate false
Only recommend you do this if running on really slow PC (that could be the case for you).
After you type the command, did the CPU usage went down?
See if that helps.
Dev