Mac and Windows file system capability

[earpin1]

I understand that macs use a different (and apparently unknown) file system when compared to PCs. My question is, if I have a 4th generation iPod, that is formatted for windows, in windows, then taken to a mac computer, and I use the external hard drive feature to put some project files on it, will there be a conflict when I take the files off of the iPod in windows? Will Windows know what to do with them? OR would I have to get one of those mac file system readers for windows(like what 1st gen ipod users use to load songs onto their iPod when using windows?)
Any comments I greatly appreciate.