Regarding the Eset find of "js HTML/Iframe.B.Gen virus", the consensus is that it is a False Positive. Are you getting any message when you startup such as "windows\system32\config\ is corrupt or missing."? But since it's a temp file, you can try either of these:

TFC (Temp File Cleaner)

Download TFC to your desktop

• Open the file and close any other windows.
• It will close all programs itself when run, make sure to let it run uninterrupted.
• Click the Start button to begin the process. The program should not take long to finish its job
• Once its finished it should reboot your machine, if not, do this yourself to ensure a complete clean

TFC only cleans temp folders. TFC will not clean URL history, prefetch, or cookies. Depending on how often someone cleans their temp folders, their system hardware, and how many accounts are present, it can take anywhere from a few seconds to a minute or more. TFC will completely clear all temp files where other temp file cleaners may fail. TFC requires a reboot immediately after running. Be sure to save any unsaved work before running TFC.

TFC (Temp File Cleaner) will clear out all temp folders for all user accounts (temp, IE temp, java, FF, Opera, Chrome, Safari), including Administrator, All Users, LocalService, NetworkService, and any other accounts in the user folder.

Then rescan with Eset.

You're welcome. You can remove the cleaning programs and old restore points:

Remove all of the tools we used and the files and folders they created

• DownloadOTCleanIt by OldTimer
• Save it to your Desktop.
• Double click OTCleanIt.exe.
• Click the CleanUp! button.
• If you are prompted to Reboot during the cleanup, select Yes.

The tool will delete itself once it finishes.

If you are prompted to Reboot during the cleanup, select Yes.

You should now set a new Restore Point to prevent infection from any previous Restore Points. The easiest and safest way to do this is:

• Go to Start > All Programs > Accessories > System Tools and click "System Restore".
• Choose the radio button marked "Create a Restore Point" on the first screen then click "Next". Give the Restore Point a name then click "Create". The new Restore Point will be stamped with the current date and time. Keep a log of this so you can find it easily should you need to use System Restore.
• Go to "Disk Cleanup" which can be found by going to Start > All Programs > Accessories > System Tools.
• Click "OK" to select the partition or drive you desire.
• Click the "More Options" Tab.
• Click "Clean Up" in the System Restore section to remove all previous Restore Points except the newly created one.

More details and screenshots for Disk Cleanup in Windows Vista can be found here.

And here's some Firefox-specific info you might want to use:

To prevent Tracking Cookies and block most ads:
For Firefox: Tools> Options> Privacy> Cookies> CHECK ‘accept Cookies from Sites’> UNCHECK 'accept third party Cookies'> Set Keep until 'they expire'. This will allow you to keep Cookies for registered sites and prevent or remove others.

I suggest using the following two add-on for Firefox. They will prevent the Tracking Cookies that come from ads and banners and other sources:
AdBlock Plus
Easy List

To block or restrict a site in Firefox:
Open Firefox> Tools> Options> Privacy> Cookies section> Exceptions> type the site domain or URL as you would in IE> Click on Block.

Using the add-ons I mentioned does some of this, but it want want to restrict a specific site, type it in this section.

Be sure to update and run a virus scan occasionally. And if the problem starts again, please let me know.

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