I'm sorry to say it will not be done by tomorrow your going to be screwed up. because there is going to be new things you have to learn and do that can't be done in a day
If you had mentioned what file type (doc, graphic) you want off the mac hdd and copying on the Pc, Windows can't read Mac format, which is a Microsoft proprietary operating system, Mac os/x is also a proprietary operating system,
I interoperate your question like this, If I'm right. You have a Western Digital Portable HD that is formatted in Mac BSD format, and you want your files off it, The way you need to do that is by downloading a copy of a Linux utility disk , Linux will read any hard drive file format.
You download the utility software, then make a boot able ISO disk. boot the disk up from the cd/dvd drive, It will then read the Window partition and the Western Digital Portable HD, You log onto the external hard drive file the file you want and the copy it (into memory) then log on to the windows partition and past it in your documents on the windows partition,
Now here is the crunch part, will windows read the file type, If it is a Mac text document the answer will be "No" it wont read it, you would have to download Open Office for windows install it on your PC, then open it up and print it out,
Here are the website you can download the Linux Utilities ISO file from
http://distrowatch.com/table.php?distribution=partedmagic
http://distrowatch.com/table.php?distribution=gparted
for the Office software here
http://openoffice.org
My advice to you would be to dump windows and move over to Linux, Linux can do everything windows and Mac can do, Linux is free to download It's up to date April 2011 there is over100 Linux distributions available with over 33,000 professional application software packages, and you can download it from here. Linux Mint has just been released today
http://distrowatch.com,