Assuming you are speaking about two partitions on the same drive, you can login to your OS X partition and locate the directory where WIN is installed, then simply drag and drop any file from WIN to OSX.
As for Microsoft Office for Windows: indeed you can use it, you have three options:
1) Boot in the WIN partition and use it normally.
2) Install it in the WIN partition, then use a virtual machine software and use it from the OSX partition.
3) Install the Mac version of Office in your OS X and enjoy.