IE6 in Win XP hanging after an URL is typed and return key is pressed

Dear friends,

I have a problem of late with IE6 (in Win XP). When an URL is typed (in the address bar) and return key is pressed or type a URL such as "yahoo" and press CTRL + Return key, the IE hangs for 10-15 seconds before retrieving the page for me.

This is happening very recently for me. I suspect it as a Virus.
I also installed Win XP SP3, but it didn't help me resolve the Issue.

Has anyone of you faced this problem before?

Please help me out. Thanks in advance !!

Regards,
Sriram