trojan, malware issue caused by banner popup ad

"Hi Everyone / Quads,

 

I have read many many threads here and on other sites.  I have tried to fix my own problem but I'm really stuck and I'm asking if you can help me.  It would be greatly appreciated.

 

I got some banner ad issue today; it tried to launch the adobe pdf reader but I cancelled it before it could launch.  This happened twice. 

 

Afterwards, my pc is running slow.  I've rebooted many times, tried safe mode, ran scans, downloaded spyware removal software, updated windows defender but nothing works.

 

I keep getting these problems: 

 

- windows live messenger stopped working popsup after window starts.
- trojan:Win32/FakeIA.C  keeps popping up from windows defender.
- windows sidebar has stopped working after startup.
- launch windows internet explorer, get a page with insecure internet activitiy.  threat of virus attack. we recommend you to protect.  click here to get full advanced real time protection continue to this website unprotected. (this keeps showing everytime i open windows internet explorer).  when i click on the first link, it goes to "defender review" site. 

 

inet explorer only works for about a minute and then, it freezes. 

 

windows defender keeps popping:  Trojan.Zlob.G

 

i ran hijack this (new version) and ran sdfix in safemode but nothing works.

 

here is the hijack this log.  can you please take a look and give me some ideas as to what to do?  i am at a point where i am going to wipe out the hard drive and install vista again.  thanks for your time."