install Adobe Shockwave screen will not go away

My Windows XP laptop showed a screen to install Adobe Shockwave this morning when I first booted up. There were the usual 3 options, Cancel, Notify Me Later and Install Now. I clicked Cancel and then I realized it was malware when the screen re-presented itself with just 2 options, Notify Me Later and Install Now. Right clicking the window in the taskbar would not bring up ‘Close’. I tried to end the task with Task Manager (CTRL, Alt, Del) and it would not let me do it. I re-started in ‘safe mode’, chose ‘safe mode with command prompt’ and did a system restore with a restore point of a couple of weeks back. I then ran MalwareBytes, CC Cleaner and Avast! scan. Everything is fine now but I was just wondering if there is a less time-consuming way to approach situations like this.

Everything is fine now but I was just wondering if there is a less time-consuming way to approach situations like this
did you try to just update and run a quick scan with malwarebytes ?

Thanks, No I didn’t. Next time I will try the moderate approach.