Which Sandbox Is Bully Proof?

Did I get your attention? I truly do need a sandbox. I think. I am new to Win 7 - old XP diehard.
My new laptop ( win 7 pro 64 bit ) was purchased for the sole use and safety to process credit cards virtually. Yes....small business. Though I do not web search unsafely, I have the need to be extremely
safe while processing. I am very confused with all the info. Checked Best protection against malware? and binged all that were mentioned. Still at a loss. Free would be great if applicable. My pci compliance is due - I always pass :). But Transarmor know "pings" merchants computers for security issues. I use Avast free - MAB so far... JRT / Ccleaner / etc used regularly..any recommendations would be helpful.

Was a good read Layback Bear . Checked out suites as suggested by kronckew. Thanks for the input all. Think that CIS may be a good choice, but have seen users complain of being buggy, quirky, and "userhateful". Anyone else have experience with it? Will it conflict with Avast?

There is nothing that is bullet-proof, every piece of software has probably bugs that can be exploited and you have to live with that, knowing and mitigating the risks. The only 100% effective way of being "safe" is to keep the computer powered off .

Backing to reality, you may look at the built-in security methods that Windows has, often more reliable than 3rd party crapware. Isolating the programs from others is easily done with a second user account. If you have critical programs, create a new user account (of course without administrative privileges) and run that program under that account exclusively. This can be done with the "run as another user" context menu of exe files.

This way the critical program is isolated from your user account, meaning that it has NO access to your private files (sandboxes sometimes give read-only access), no permissions to do system-wide changes and no possibility to interact with anything else in the system. This gives in practice most benefits sandboxes have, without the need of external software. This is the approach Android uses for added security, BTW.

Of course that's not immune to other problems. Malware that has managed to have system-wide access also harms you in this case, but then you have greater problems to begin with. Just be sure to use that extra account for running that program and nothing else, and of course don't accept UAC prompts from it.

Some very good info indeed. My main concern is safety while online processing thru virtual gateway. Maybe I am confusing myself over the sandbox need. I do not save customer data. I do a complete clean / virus / malware before and after each online gateway session. What would be the most reliable option based on online security, besides a dedicated user account?