how i can remove the <iframe virus from my codes

To enable Task Manager see either of these links.  
http://antivirus.about.com/od/windowsbasics/ht/taskmanager.htm
http://windowsxp.mvps.org/Taskmanager_error.htm
To scan your system for possible viruses/malware please read the following.
I recommend downloading and updating malwarebytes.
You can get it free from www.Malwarebytes.org
Prior to running Malwarebytes (or any other anti-virus/malware suite),
disable System Restore. Directions can be found here:
http://support.microsoft.com/kb/310405
If you are unable to view the above link follow these steps.
Click Start, right-click My Computer, and then click Properties.
In the System Properties dialog box, click the System Restore tab.
Click to select the Turn off System Restore check box. Or, click to select the Turn off System Restore on all drives check box.
Click OK.
When you receive the following message, click Yes to confirm that you want to turn off System Restore:
You have chosen to turn off System Restore. If you continue, all existing restore points will be deleted, and you will not be able to track or undo changes to your computer.
Do you want to turn off System Restore?
After a few moments, the System Properties dialog box closes.
Once updated, reboot into Safe Mode (F8 at startup) and run a scan.
You should do this with your current antivirus product as well.
If the above steps fail to remove the threat,
you may need to download and run Combofix.
The free download and directions can be located here.
http://www.bleepingcomputer.com/combofix/how-to-use-combofix
As noted in the directions, prior to running Combofix or any other anti-malware/anti-virus application please stop your anti-virus and anti-malware programs. Combofix should be saved to and run from your desktop.
You should rename the anti-malware suites to a different name prior to downloading as some threats can prevent them from running with their default names.
When you have finished running your scans and the threats have been removed enable System Restore.
Steps to turn on System Restore:
Click Start, right-click My Computer, and then click Properties.
In the System Properties dialog box, click the System Restore tab.
Click to clear the Turn off System Restore check box. Or, click the Turn off System Restore on all drives check box.
Click OK.
After a few moments, the System Properties dialog box closes.
There is also a trusted and free utility that shows you what programs are configured to run during system bootup or login, and shows you the entries in the order Windows processes them. These programs include ones in your startup folder, Run, RunOnce, and other Registry keys. This is handy if you are receiving rundll errors or pop ups when you log on.
AutoRuns for Windows
http://technet.microsoft.com/en-us/sysinternals/bb963902.aspx
If after running any of the suites above you find that your internet connection fails (is broken) please perform the following steps.
Restart your computer and test your internet connection.
If it does not work, then click Start ->Settings and Control Panel.
Select Network connections. Locate your connection and right click on it.
In the menu click the Repair option. When the repair proccess has finished, your connection should be working again. Reboot to test.
David