What makes Mozilla better than what is installed?
When I come here, usually I'm "pretending" to know what I'm talking about when it comes from football. Computers are my livelihood.
Mozilla / Firefox (for the sake of argument, I'm going to refer to it as just firefox) is better than "what is installed" (Internet Explorer) for a variety of reasons.
Speed is one reason. Firefox is faster because it uses less system memory, and it's designed to be a web browser. Internet Explorer isn't just a web browser. It's also a file browser. It just happens to also browse the web.
Firefox is much more secure. Internet Explorer is "attached" to the Windows Operating System. If IE crashes, windows essentially crashes. If IE get's "hacked" remotely, windows can essentially get hacked remotely (be warned of ActiveX). Firefox doesn't inherit the underlaying security flaws of the Windows OS. Firefox runs on top of, not within, windows. So if Firefox get's "hacked", windows may (I say "may", because windows is about as secure from "hackers" as a wal-mart with it's door off it's hinges in post katrina New Orleans)
Firefox is also "open source". Internet Explorer is not. Which means, that anyone can go to mozilla.com and download the computer code on how firefox is built. We can see how it runs. Anyone can improve upon, fix, and secure firefox. Since Everyone can see it, something doesn't stay broken for long. Internet Explorer is closed source. Which means that only certain people in Microsoft can see the code for Internet Explorer. Open Source security Vs. Closed Source security is a touchy subject, but can best be explained like this:
If you lived in a glass house, everyone could see the mess you would leave around your house. Assuming that you thought your image to the neighborhood was important, you'd keep your entire house spotless. Everyone knew what you had, and where you have it. Nothing in your house is a secret to any one. If someone sees your big pile of dirty laundry / dishes / etc, everyone will make fun of you at work the next day. Especially if ate off of a dirty plate or didn't wash those clothes before you wore them again. Thats the "glass house" example of open source security.
Closed source security is like a normal house. No one knows but you if you wore those pants twice. Closed Source security implores the "Security by obscurity" model. Meaning, as long as you can't see it, it's secure, right? If we don't tell anyone that we leave the front door to our house unlocked, no one will break in, right?
The problem really with Internet Explorer, and Microsoft in general is that no one outside the company really knows how many security holes, flaws, and bugs their software has. Would you put your money into a bank that "might" have a secure vault? Or just "might" have all the doors locked at night? I wouldn't.
Sorry to get off topic, but yeah, you may have some spyware.
Try a program such as:
ad-aware (free)
spybot search and destroy (free)
spysweeper ($30 at wal-mart, but a great program).
If your copy of windows was "illegal", you'd get little pop-up windows in the lower right hand corner saying "this may be an illegal copy...blah blah blah...give us more money".
Microsofts EULA (end user license agreement) says you can transfer the license of a non-OEM copy of Windows. Meaning, that if you have a copy of windows that came with a Dell, Gateway, etc... it's an OEM, and according to Microsoft, is not yours. "The right to use that copy of windows XP" still belongs to the original person who bought it. If it's a non-oem disk, then yes it's yours through resale from the original owner. The easiest way to tell if it's OEM or not is to see if it says anything about Gateway, Dell, etc...