I have been using the internet for last few years and everything worked fine. However, until few months ago, I could not defend from all sorts of viruses and adwares. I reinstalled OS several times but it did not help me for a long. After a day or two on the Internet, I have the same problems again. I obviously have to change my Internet Explorer. How often should I change my password and username?
Of course, there are other browsers beside the Internet Explorer. Some of the most popular are MSN and Opera. Many users also claims that they are so much better and safer then the Internet Explorer. I personally disagree with them. I am also on the Internet many hours per day, and my favorite browser is Internet Explorer and I do not have any problems. I do not think that you should change your Internet browser. To solve your problems you need some anti-spyware software like SpyBot S&D, which is completely free. Second thing you need is some good anti-virus software which is also free. I personally use AVG 8.0 and I am completely satisfied. If you have Windows XP, you also have to check do you have Service Pack 2 installed. If don't then download and install it. All those things will not slow your machine much but will give you enough protection. For home computers, changing password on three-month period will do the job.