Hello,
Am Oti by name, i bought one of your product; dell inspiron window 7, last year, presently is being working very slow, and i perceive is virus, i need an antivirus dat is compatible with the system,can you be of help please.
If your system is slow that doesn't mean your computer is infected.
Window 7 has a built in antivirus "Window defender"
You can use free option like Avast free
Or If you wanted complete security suite than try
BitDefender Internet security or Trendmicro Internet Security