The most quick solution did you have is to create a partition with a filesystem it is compatible with both OS (as my suggestion NTFS is a good choose), like this the data are available on both OS.
In this case you have to think that the files created have to follow the windows rules, you have to consider NTFS as filesystem case insensitive; so a file of folder stored there called
DATA and another called
data in the Linux OS are two different path but for the windows OS there have no difference between
data, also the permission are different between the two OS, so it will make harder to manage permission correctly; as far I remember NTFS partition mounted with ntfs-3g driver give permission rwx to all.