Well after moving to U.S., my laptop was badly affected with all kinda viruses.... So just thought of sharing with you all some of the tips on anti viruses....
* Before you start downloading any anti virus, make sure that you download it from genuine provider. Now a days, many viruses float on internet which claim as anti viruses but in reality they are viruses & can cause more damage. As far as possible, try to download from http://download.cnet.com/ which is the most secured place to get free anti virus softwares.
* After machine gets infected with virus, some of deadly viruses stops browsers functionality, downloads etc. So it is always a good idea to take a proactive approach & get anti viruses loaded on your machine when its working in fine manner.
* Spybot Search & Destroy is free anti virus which takes care of many scarewares & spywares. It can be downloaded for free from http://download.cnet.com/3001-8022_4-10122137.html
* Malware Bytes - free software
* Semantec
* Mc Afee - Bank of America a/c holders get one year free subscription. Licensed version of Mc Afee can be downloaded from bank of america's web site after logging into a/c.
* Norton Anti Virus
* Registry Mechanic - free software
* In case your windows XP files association got corrupted. e.g. exe files don't work & opens dialog box of "Open with" then in such cases respective registry needs to get fixed. Those reg files can be downloaded from http://www.dougknox.com/xp/file_assoc.htm Just double clicking .reg file will install registry.