Recently, my computer had a lot of trojans and other viruses. I installed Norton Antivirus, as well as other DLed programs and ran them. Norton somehow deleted one of my startup files, and in doing so, I wasn't able to get onto my laptop. I reinstalled WindowsXP from a friends disks (I'm in Japan and all of my startup disks and program disks are back in America). I am still able to access my old files (pictures, music, etc.) but none of the old programs are here (like Microsoft Office). Is there any way to copy program files from the old system onto the new Windows?

Also, how can I keep my computer from getting as bad as it did? Any ideas?

Thank you!