you need a good antivirus system in addition to whatever OS you decide to have ,64bit is better (more secure) within itself ,but as far as viruses are concerned it is as vulnerable as 32bit . a lot of 32bit softwares wont run ,or are simply not supported on 64 bit so it wont (run everything) quite a lot of users had to buy new networking devices ,or printers etc as many older models are not supported in 64bit. 64bit is the way to go Yes ,as long as 3rd party software and hardware makers play ball , they have been slow to take it up so far ,although there is a sign at last with windows 7 of much less compatability issues . an interesting thing about win 7 is that whatever version you buy ,the whole pack is installed ,what version you activate ,determins what functions are switched on or off by default . Unless you plan to upgrade to say 8gb of ram or plan to use 64bit only 3rd party softwares, you wont see hardly any benifit to 64bit.