Apple designed the Mac with people like you in mind. that is, people that are switching from Windows and are not sure how stuff will work now. they developed tools and guides to help you do that transition very easy. In the worst case, you don't even have to do anything, just bring your PC to an Apple store and they'll do everything for you.
but to answer your questions:
1) actually, the Office for Mac (2004) has received better reviews than the one from Windows. but to your question, you will need absolutely no conversions of any kind to view your Office documents on either Mac or PC.
2) Outlook for Mac is called Entourage. I believe when you first run it, it asks you if you want to transfer your account from Outlook. if it doesn't, there is a ton of tutorials out there as well as their help file is very good. the transition will be very easy! as for the Blackberry server, since it's just a matter of setting it up as your mail server, this shouldn't affect anything either (should be same setup as on your PC).
3) Absolutely! your new mac will come reinstalled with iPhoto (
http://www.apple.com/ilife/iphoto/) which will help you organize all your pics with an ease. just choose import photos from the menu and that's it. in addition to iPhoto, you can always install an image viewer of your choice, there is plenty to choose from.
4) to transfer your music, just copy it on the Mac, launch iTunes and add them to your library. iTunes for Windows is a 100% replica of iTunes for Mac so you'll find it very easy to use. Not sure about the iPod (i don't have one) but I'm sure there is a help file discussing this issue.
5) Depends which one you get. All new Macs come with Ethernet (internet) ports and 54g wireless cards.
6) Mac OS X can read pretty much any file system (well, not any) but external hard drives are usually formatted in FAT32 file system and that will basically be plug-n-play on your new Mac.
you can find a pretty nice summary about this here:
http://www.apple.com/macosx/switch/