I have been using bitcoin core on windows for most of a year.  I guess it is time for me to migrate that to linux.  That said, having the full block chain on your own computer helps prevent hacking as well as the health of bitcoin since you are another copy for the system to compare off.  The main reason for not using windows is all the viruses that can intercept what goes between your hands and the internet (Kano, can you confirm).  Keep your firewalls, virus scanners and other security measures in place (including safe browsing and not opening unknown emails) and it will help for the short term.  When you can swing the money and time, probably best to migrate it to linux (which I will be doing now too).