it is quite possible to get infected by reading an email without opening an attachment (see the Bubble Boy virus and successors), though much more common to get infected by a word or excel document, since macros are easily hidden in these. To prevent this happening open the attachment with a viewer, rather than the microsoft application which will automatically run the macro.

more bad viruses that do real harm are spread by floppy than email in reality, particularly nasty boot sector viruses.

XP is a huge step backwards in security terms, generally speaking, because of their stupid authentication and auto update type features that no one wants or asked for.

I have all the anti virus programs but never use them because they interfere too much with the way I use the pc. I do NOT recommend others do the same.

I just throw away all attachments from people I don't know, and was not expecting. Besides I can boot from a cd and restore the entire system in 5 minutes from a ghost image, the best protection you can have, but in years of computing have not had a single infection get through yet, so do not get paranoid about viruses, there is much exageration and myth put about by newspapers who don't know what they're talking about and vested interests wanting to sell you solutions, plus much hoaxing.

AVG and Sophos probably have the best reputation amongst the professionals. If you can live with Norton taking over your system, (I can't) stick with it. McAfee has not got a good reputation, and PCcillin never had.

The next generation of html email programs will open a new door to java and vbs attack so will need to be intelligently designed to be safe i.e. if done by microsoft will be guaranteed full of huge security holes.