If you need a file from your Linux partition while running Windows, there’s an easier way than to boot into Linux, copy the file to a USB “thumb drive”, boot Windows and paste. Rather, you can install an Ext2 file system driver for Windows. “Ext2 IFS” supports reading and writing to Ext2 partitions from Windows. And you can write to the Linux swap partition from Windows if you want to recycle your disk space and use the same swap space both for Linux and Windows (just don’t try to hibernate from one system and reboot to the other!).

Update: Just a comment. Modern desktop linuxen usually use the Ext3 file system. Ext3 is “just” Ext2 with journalling, meaning that if your computer suddenly crashes amidst a disk operation, the file system can be pretty reliably rebuilt using the journal. Or put differently, this is probably precisely the driver you want if you want to be able to read your Linux filesystem from Windows.