Hi marinoumali,
First, download, install, update, and run Malwarebytes
http://www.malwarebytes.org/mbam.php to verify there is no malware affecting your system and causing this trouble. Though using only one program isn't proof, if it comes back clean (or found and removed anything but left nothing it couldn't handle), that's enough to proceed for now.
The problem installing Kaspersky may be that Avira isn't properly uninstalled. Try using Revo Pro
Revo Uninstaller Pro - Uninstall Software, Remove Programs easily (you'll have to get the trial version because you have 64-bit and then cancel within 30 days to avoid paying for it if you don't want to keep it) to uninstall/remove Avira. Use the Advanced mode. When checking the boxes on what to remove, make certain each applies only to Avira and nothing else - sometimes it presents options which should not be deleted - if in doubt, do not check the box. If you did this, then see if you can now install Kaspersky. If not, read on.
Can you access the internet? Is the system date/time correct (I mean within a minute or two - if not, please fix it)? Add the application fact.exe to the Windows Firewall exceptions. Then try again.
If that doesn't work, in IE go to to Tools / Internet Options / Advanced and make sure to check the boxes next to SSL 2.0, SSL 3.0 and TLS 1.0. Then close IE and reopen it and see if that helps.
If that doesn't work, try
a clean boot http://support.microsoft.com/kb/929135. If the problem goes away then it's just a matter of tracking down the culprit causing the problem. Follow the procedures in the article. Once found, delete, remove, deactivate, or uninstall it. Once done be sure to reset Vista back to normal status as explained in the procedures. If the problem occurs in clean mode then just restore the system to normal status and reboot - this solution is not going to work.
Boot into Safe mode with networking and see if the problem occurs there. Either result helps us narrow down the search for the cause.
If that doesn't work, try the following general IE troubleshooting guidelines:
Try reviewing the following article:
Tips for solving problems with Internet Explorer
http://windows.microsoft.com/en-US/windows7/Tips-for-solving-problems-with-Internet-Explorer
If that doesn't resolve the problem, then try the following two procedures in the order presented:
Troubleshooting and Internet Explorer’s (No Add-ons) Mode [Applies to IE7 & IE8 in all OSS]
http://blogs.msdn.com/ie/archive/2006/07/25/678113.aspx
Does the behavior persist if you Reset IE Advanced settings (RIES)?
http://support.microsoft.com/kb/923737
How to optimize Internet Explorer
http://support.microsoft.com/default.aspx/kb/936213/?p=1
How to troubleshoot Internet Explorer issues in Windows Vista and in Windows XP
http://support.microsoft.com/kb/936215
Hopefully, one of these procedures will resolve your problems with IE.
I hope this helps.
Good luck!