Hi Ivy,
Unfortunately, you are experiencing a very common problem. No one program seems to be able to get rid of everything.
You are also correct about the so-called "free" programs. Most of them only scan your computer, tell you what's wrong, and then tell you that you have to upgrade before you can clean the problems.
There are some excellent programs that I recommend very highly. (Incidently, the best way to determine which ones DO work is to get recommendations from others who have successfully tried them.)
AdAware is a good free program that does work well. It won't necessarily get everything, but it gets a lot and cleans it, too.
Windows Defender, formerly called Microsoft Antispyware, is an excellent piece of software that is also free and really works well. I have had great success with this one.
NoAdware isn't free, but it's an excellent investment for your computer security. Yes, I am an affiliate for this one, and would recommend that anyone buying it become an affiliate, too. Like you, Ivy, I've bought a few others and have been very disappointed with them. However, this one works great, and as far as I'm concerned, is a MUST HAVE for your computer.
To sum up, I recommend that you get all three pieces of software and run them all, one at a time. This should clean out any malicious software presently running on your computer.
Also, make sure your antivirus and firewall software is up-to-date. If you're running free antivirus and firewall protection, which can be a bit dicey, I would recommend
AVG Antivirus and
Zone Alarm Free. Sygate Personal Firewall is better, but Sygate has been bought out by Symantec and the firewall is no longer free.
I hope all this is helpful to you, Ivy. If you run these programs and your computer is still slow, it's likely time to run a product like Norton Systemworks from
Symantec or
Registry Doctor, available from Download.com. These products may look expensive, but they work well and will save you a ton of money in bills from the computer repair people!
God bless,
Dave