Helpful Links Regarding Flashback Trojan and Virus Protection
An excellent link to read is Tom Reed's Mac Malware Guide.
A link to a great User Tip about the trojan: Flashback Trojan User Tip.
To check for the trojan: Anti Flashback Trojan 2.0.4.
A Google search can reveal a variety of alternatives on how the remove the trojan should your computer get infected. This can get you started. Or the preferred method is to use Apple's protection tool: Flashback Malware Removal Tool 1.0.
Or, open Software Update. If you do not have the Apple protection software installed it will download and install it via Software Update. If no update appears that means you either already have it installed or it isn't needed for your system. The software is only available for Leopard, Snow Leopard, and Lion versions of OS X.
Also see Apple's article About Flashback malware.
For general anti-virus protection I only recommend using ClamXav.
For the DNS Changer malware see the following:
Just noticing some slowing of performance & some occasional pop ups asking if I want to clean my Mac especially when I am in email account.
Sounds like MacKeeper. Ignore those pop ups, even when they tell you they've found something wrong with your computer (they can't). Just an aggressive advertiser trying to convince you to buy something you do not need.
As others have told you, a fully up-to-date OS X 10.6.8 is all you need to protect you against all currently known OS X malware. Could some fancy A-V software warn you of tomorrows threat? Perhaps, but I have only observed that once in all the time I've been monitoring the situation.
I do agree with MadMacs0 - 100%.
as to your slowdown issues, why don't you check what's loading in your login items and delete the ones you don't need.
check activity monitor under all processes and highlight the ones using the most % CPU and hit quit process.
then go on to disk utility and click on verify disk. once you've done that, verify disk permissions. repair if needed.
restart your macbook.
hopefully it speeds it up a bit.
a RAM upgrade is also a good idea.
Note that this thread is over two years old and much has changed since then.
How do I remove pastaleads malware from my macbook pro OS X 10.9.5?
Never heard of any OSX malware with that name. Where are you seeing "pasta leads"? It sounds like some sort of Adware rather than malware. If that's the case you need to run AdwareMedic which will remove all currently known adware safely and efficiently.
If that doesn't work, you will almost certainly need to start a new thread as nobody but some of those responding to the OP will ever see this. That's just the way this forum works best.