Even when I have activated one web site, under the Task manager shows more than one iexplore.exe *32 processes and pc freezes and cannot access anything on the pc until I terminate the internet processes using 'end task' of the task manager. Eventhen the problem comes back after a while.
baldyx, unfortunately there are lots of potential causes for that problem such as corrupt temporary Internet files, malware infections, or malfunctioning third-party browser add-ons. You've mentioned the process iexplore.exe *32 as being the culprit so I'm assuming from now on that you're using Internet Explorer and the 64-bit version of Windows 7 or perhaps Vista.
To deal with the first two, try this:
Go into Internet Options, and in the "Browsing" section, click the "Delete" button, make sure that only "Temporary Internet Files" is ticked then click the second "Delete" button.
When you've done that, go here, download Malwarebytes Anti-Malware (if you don't already have it), install it, update it, run a "Quick Scan" and remove everything it finds. Note that if you're prompted to start a free trial of the MBAM Pro version then you can decline their invitation.
There's a way to tell if IE itself is broken or whether it's being affected by a rogue add-on and that's to use the "No Add-ons" version of IE for a while. In case you don't know what an add-on is then it's a small program that adds extra functionality to IE. Adobe Flash is an example of an add-on you may have heard of.
If you're keen to troubleshoot this then you'll find that special version of IE via the Start button -> All Programs -> Accessories -> System Tools -> Internet Explorer (No Add-ons). Use it for a while and report back your findings and we can take it from there. Note that some webpages may not display properly because all add-ons have been disabled.