Thanks you looking over the other thread, unfortunately I am hoping more people can add their input, it will be more rebust in time.
ubuntu ultimate is a third party mod on ubuntu and is not officially supported by the community so it may not be your best best, but all mods present in it can be applied to any ubuntu installation to make it just as friendly.
Re: Compatibility: windows apps are differently than Linux programs, so installing a windows program would mean doing it through an emulator, and some emulators cannot run on 64-bit installations. The primary emulators for you to look at in regards to your windows apps are wine (http://www.winehq.org/), cedega (http://www.cedega.com/) and crossover games/office (http://www.codeweavers.com/products/cxgames/). The document compatibility is pretty good among office formats, most opensource productivity software can read and write to MS format (pre Msoffice 2007). One thing you may want to remembers is most software on Linux distros is free and some are more powerful than their expensive windows based counterparts, before you start thinking that you have to use an MS based app try some opensource alternatives.
As for the cli vs gui comment, all distros run on a gui and cli, many cli apps only translate commands to the gui apps. No matter that distro you choose you will have the option to use the gui, but some like ubuntu have nearly removed the need for a normal user to use the gui.
My recommendation for now is to install ubuntu 9.04 with the MS installer (named wubi) within an MS partition to try it out without devoting too much time, when you insert the disk when windows is running it will open a window that has an option "install in windows" this will be slower than partition based, but it is easier to remove. Play with that for a while, then when 9.10 is released you can install it in it's own partition. I am running 9.10 beta on another partition , the changes that I can see are it is faster, prettier and utilizes less resources than 9.04. Most notably the boot speed, it boots fast.
After you get familiar with the tools and functions in a more user friendly distro then it may be of interest for you to try Slackware, but it is not for new users because it requires alot of reading and learning, but it you are willing to allocate the time and effort to learning it is a very stable distro with a good community.