Q: I'm moving from Windows back to Mac, looking for advise on best IMac.

Currently running a Windows based Intel Core 2 Quad at 2.56ghz with 4GB RAM and 750GB hard drive that is 1/3 full. Considering 21.5 Imac but need to decide on Fusion drive or more RAM. Use PC for mostly email, calendars, internets, pictures, itunes, light excel and word applications, some PDFs and skype. Want this investment to be relevant for 5+ years.