To Brown Town,
My guess is that you don't just have spy ware, you have an infestation of it. The long term consequences of running a computer with a inadequate security set up.
Is it safe to do on line banking with your computer? And thats a maybe and maybe not because only certain types of spyware or should I say malware is designed to be a danger to to online banking type activities. Since you don't know what you have, I would say its not worth the risk. But you should not judge by pop ups, they are somewhat normal, just go into your web browser and stop them there.
But you very much remind me of my experience of buying a used computer at a very attractive price on ebay. It came with all the wondrous hardware advertised. And as an extra measure they threw in about 4000+ pieces of malware at no extra charge. I would not even let that computer onto the internet until I had run adaware, spybot, and avast with old definitions. Thats when I discovered how infested it was and just that act got rid of about 85%. New definitions got rid of another 5%. Then I ran them in safe mode and got rid of a bunch more. And was still infested.
The point being, there is nothing wrong with adaware and spybot S&D. But they are not all inclusive and the real nasty malware knows how to hide. Its far easier to prevent malware from installing than it is to remove once installed.
My next step was to install, update, and run superantispyware, A2, AVG anti malware, windows defender, and other similar programs that got some more. Then I tried various online scans and that got some more. And some root kit scanners. And long after every online scanner on the planet pronounced me malware free I still had a dozen left. A hijack this logfile got those on spywarewarrior.com. Stubborn me, I was bound and determined to get rid of the malware without a clean install, but 20 20 hindsight, I really should have done the clean install..
But in terms of protecting my PC once clean, thats easy. Its all in the security resource thread and a layered defense. Although it did not exist at the time. But in terms of just adaware and spybot alone, they are just a tiny start. And the biggest single thing you can do is use a limited user account---with a full software restriction policy if you have XP pro. If it can't install it can't infect.