Can malware move from Windows to Mac I recently got a Mac, and am transferring files from my old Windows laptop which had kept freezing with very high hard-drive activity, and may or may not be infected with malware. I'm wondering if there's a chance of my Mac being infected by malware from photos, documents, videos and music transferred from a Windows machine? 

If so, which antivirus would you recommend me to get on my Mac? Are Sophos and Avira any good?
This answer reflects the situation at the time it was written (beginning of 2013) and may be different today. Please don't assume that it is still correct for current malware implementations

The short answer is "No, your Mac should not get infected".

The a bit longer answer is "it depends". You should be fine with photos, videos and music, but there might a very small risk with documents (depending on the format) and anything html-related (which might access a malware server or something). But given the current state of malware on OS X I wouldn't worry too much.