The y2 entries are part of this:
FF - Ext: Yontoo Layers: plugin@yontoo.com - %profile%\extensions\plugin@yontoo.com

This plugin is used with Facebook..

The Yontoo.com site is not well rated by WOT. All areas of 'vendor reliability', 'privacy' and 'child safety' are showing "Caution.".

It's possible that this was bundled with another progrm and added to the system without your knowledge or permission. We call the 'Foistware.' It not a virus or malware, but the potential of exposure to the system is high for malware.

Comments from users:
"Yontoo is an unnecessary program that doesn't register within IE. That means it's probably tapping into more than just Internet Explorer's functionality. And is also why it won't work in Firefox, Chrome, etc... too secure. It's associated with PageRage"

"There is absolutely ZERO value to this software. in fact on the contrary it only benefits the software writer by getting ad revenues."
=========================================
Please download OTMovit by Old Timer and save to your desktop.

• Double-click OTMoveIt3.exe to run it. (Vista users, please right click on OTMoveit3.exe and select "Run as an Administrator")
• Copy the file paths below to the clipboard by highlighting ALL of them and pressing CTRL + C (or, after highlighting, right-click and choose Copy):
  
  Code:

  :Files 
  C:\Documents and Settings\Antoinette\Application Data\AVG\Rescue\PC Tuneup 2011\110312225326546.rsc
  :Commands
  [purity]
  [emptytemp]
  [start explorer]
  [Reboot]

• Return to OTMoveIt3, right click in the "Paste Instructions for Items to be Moved" window and choose Paste.
• Click the red Moveit! button.
• A log of files and folders moved will be created in the c:\_OTMoveIt\MovedFiles folder in the form of Date and Time (mmddyyyy_hhmmss.log). Please open this log in Notepad and post its contents in your next reply.
• Close OTMoveIt3

If a file or folder cannot be moved immediately you may be asked to reboot the machine to finish the move process. If you are asked to reboot the machine choose Yes.
======================================
You need to be more discriminating of the sites where you're getting downloads.I suggest you put this Site Advisor on the system asnd don't click on any site for anything unless you see a Green Light:
The Web of Trust-(WOT) add-on is a safe surfing tool for your browser. Traffic-light rating symbols show which rate the site for Trustworthiness, Vendor Reliability, Privacy, Child Safety.Your online email account – Google Mail, Yahoo! Mail and Hotmail is also protected.

Every time you do a search and the screen comes up with the sites, they will have the rating light:
Green (2 shades)> Good to go.
Amber/Yellow> use Caution,
Red> not advised.
===========================================
Removing all of the tools we used and the files and folders they created

• Uninstall ComboFix and all Backups of the files it deleted
• Click START> then RUN
• Now type Combofix /Uninstall in the runbox and click OK. Note the space between the X and the U, it needs to be there.
  

• Download OTCleanIt by OldTimer and save it to your Desktop.
• Double click OTCleanIt.exe.
• Click the CleanUp! button.
• Select Yes when the "Begin cleanup Process?" prompt appears.
• If you are prompted to Reboot during the cleanup, select Yes.
• The tool will delete itself once it finishes.

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Note: If you receive a warning from your firewall or other security programs regarding OTC attempting to contact the internet, please allow it to do so.

Note: If any tool, file or folder (belonging to the program we have used) hasn't been deleted, please delete it manually.
------------------------------------------

• You should now set a new Restore Point and remove the old restore points to prevent infection from any previous Restore Points.
• Go to Start > All Programs > Accessories > System Tools
• Click "System Restore".
• Choose "Create a Restore Point" on the first screen then click "Next".
• Give the Restore Point a name> click "Create".
  
• Go back and follow the path to > System Tools.
  [*]Choose Disc Cleanup
  [*]Click "OK" to select the partition or drive you want.
  [*]Click the "More Options" Tab.
  [*]Click "Clean Up" in the System Restore section to remove all previous Restore Points except the newly created one.

Empty the Recycle Bin

Let me know if you have any questions.

Your system is clean! Please follow my directions in my Reply #22 to "Removing all of the tools we used and the files and folders they created."

Tips for added security and safer browsing: (Links are in Bold Blue)

1. Browser Security
   [o] Safe Settings (Please ignore the suggestion to use the Registry Editor in this section "Creating a Custom Security Zone")
   [o] ZonedOut. This manages the Zones in Internet Explorer. (For IE7 and IE8, Windows 2000 thru Vista. No Windows 7)
   [o] Replace the Host Files
   [o] Google Toolbar Pop Up Blocker
   [o]Web of Trust (WOT) Site Advisor. Traffic-light rating symbols show which rate the site for Trustworthiness, Vendor Reliability, Privacy, Child Safety.
   
2. Have layered Security:
   [o]Antivirus :(only one):Both of the following programs are free and known to be good:
   [o]Avira-AntiVir-Personal-Free-Antivirus
   [o]Avast-Free Antivirus
   [o]Firewall (only one): Use bi-directional firewall. Both of the following programs are free and known to be good:
   [o]Comodo
   [o]Zone Alarm
   
3. Antimalware: I recommend all of the following:
   [o]Spywareblaster: SpywareBlaster protects against bad ActiveX.
   [o]Spybot Search & Destroy
   
4. Updates: Stay current:
   [o] the Microsoft Download Sitefrequently. All updates marked Critical and the current SP updates.
   [o]Adobe Reader Install current, uninstall old.
   [o]Java Updates Install current, uninstall old.
   
5. Tracking Cookies
   Reset Cookie:
   [o]For Internet Explorer: Internet Options (through Tools or Control Panel) Privacy tab> Advanced button> check 'override automatic Cookie handling'> check 'accept first party Cookies'> check 'Block third party Cookies'> check 'allow per session Cookies'> Apply> OK.
   [o]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. (Note: for Firefox v3.5, after Privacy click on 'use custom settings for History.')
   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
   [o]For Chrome: Tools> Options> Under The Hood> Privacy Section> CHECK 'Restrict how third party Cookies can be used'> Close.
   
6. Do regular Maintenance
   Clean the temporary internet files often:
   [o] Temporary File Cleaner]
   or
   [o] ATF Cleaner by Atribune
7. Restore Points:
   [o]See System Restore Guide
8. Safe Email Handling
   [o] Don't open email from anyone you don't know.
   [o] Don't open Attachments in the email. Safe to your desktop and scan for viruses using a right click
   [o] Don't leave your personal email address on the internet. Have a separate email account at one of the free web-based emails like Yahoo.

Please let me know if you find any bad link.