Formatting to reiserfs in Windows XP isn't going to help you much either.

You could setup permissions for your drives when you right click on a drive and go into Properties > Security. Of course it would be favorable to password protect your Windows login or else anyone could log onto your account and access the drive you've protected.

If you can't seem to get to the Security tab in Properties, first go to any explorer window and go to Tools > Folder Options > View > and untick Use Simple File Sharing. Go back to the Properties Window and it should appear.

EDIT: What he said.