Hi there, hi there.
I have been using a dual-boot Windows / Redhat Linux system for many years now. Compatibilty between windows and linux apps have certainly come a long way since the first release of the windows emulator for Linux WINE.
I run the Lotus Notes 5 windows client under Linux with KDE Desktop using the latest version of Wine. Although it works, some features do not respond the way it should uner the native windows OS, i suppose due to the libraries that ship with wine.
As far as running Ms-Office apps under linux I think you might be a bit optimistic. Linux is a open source OS with support for thousands of open source applications developed for Linux. if you want to explore the world of Linux I would suggest you rather experiment with some of the linux applications. On the office application side you can try OpenOffice.org, previously called StarOffice. It offers about 80% of the features of MS-Office, and it's free. On the DB side you can play with MySQL, PHP and Perl.
If you are a newbie on Linux you should expect to feel a bit lost initially, especially when you dig into the shell, kernel side of things. Luckily the new Linux distributions are very easy to install and configure and you should be up and running in no time. Visit the website of the distribution you wish to install and verify the hardware compatibilty of your computer. Issues like display and monitor driver problems can sometimes make your life a misery, but it's all part of the fun.
Redhat, SUsE and Mandrake are very good choices for a Linux desktop sysem.
Good luck, and up the Penguin!