My old laptop is showing signs of age, so I bought a new one last week. It's an HP laptop running Windows 7 Professional. I have managed to infect it with ad malware and when I do a search for information on how to get rid of it, I see a bunch of links for websites that may not be legit. Can anyone recommend a trustworthy website that provides info on how to remove malware?

Here's the long story...

I installed Microsoft Security Essentials on the new laptop, since it seemed to work well on my old laptop. Then I wanted to install Firefox for my browser. I searched for Firefox on Bing.com and clicked on the first link it returned. I don't know if I was just too tired to realize I was doing something wrong or if somebody did a really good job of spoofing Firefox, but I ended up installing something else -- I think it was called Vosteran. When I realized the new browser was not Firefox, I uninstalled it (using the program uninstaller on the Windows Control Panel) and then found and installed the real Firefox.

Things worked fine with secure (https) websites, but with others I got pop-up ad windows that froze the screen. I checked that the Firefox pop-up blocker is on. Then I saw the words "dynamo combo" on the top of the pop-ups. I did an internet search, found a bunch of results saying it was ad malware. I think it was installed along with the bad browser. Through the Windows Control Panel I found and uninstalled Dynamo Combo. The Control Panel uninstall list showed a second program installed at the same time, I don't remember the name but it began with an E, and I searched Bing for that and found it also was malware so I removed it. After each uninstall I rebooted the laptop. Then I did a full scan with Microsoft Security Essentials and it found nothing wrong. I was able to browse various websites using Firefox with no problems and no sign of malware.

Then I was searching for some hotel information on booking.com. My search completely froze the browser and the pc. I couldn't get the task manager to open (for some reason Microsoft changed the way to open it with this operating system, which I didn't know at the time) so I pressed the power button to turn the pc off, then turned it back on.

And now the pop ups are back. But dynamo combo is not showing up on the Control Panel list of programs that I can uninstall -- there's nothing there except Firefox, Microsoft Security Essentials, some software I downloaded for work and some Microsoft updates. So I have no idea how to get rid of the malware.

I can do a search on "dynamo combo removal" and it returns a bunch of results, but none of the results is for a website that I've heard of before. I'm reluctant to click on any of then and follow their advice because I'm worried they will just end up exposing me to more bad software.

I tried to find advice from Microsoft's website, since I'm using their security software, but can't find anything there.

I appreciate any advice. Thanks!!