I have recently bought Morrowind and Oblivion on Steam. I have been playing Skyrim for a long time and enjoying is immensely.

I tried Morrowind for a short time before (a loooong time ago) and now I would like to start it over and play it "seriously". Since it's an older game I suppose there are many very stable and good mods for it. The first (and maybe the only) I would like to install is MGSO 3.0. I only want to improve the graphics a bit, while keeping the atmosphere as faithful to the original as possible. I don't really care about anything else.

So my questions is, to those that are expert in the subject, is there any critical problems with MGSO? Will I be able to play it from the beginning to the end without some fatal, game-breaking bug? I heard many good things about it, but I would like to make sure.

Thank you in advance!

First of all, Welcome to the forums

MGSO is a very good 'compilation' of mods with auto-installer. It doesn't alter gameplay or things like that.
Make sure you install tis patch --> http://download.fliggerty.com/download-13-726

As far as bugs, there is none apart from those fixed in the temporary patch. MGSO also includes Morrowind Code Patch which fixes many quirks and problems with morrowind and Morrowind Patch Project, which fixes most of major bugs from the game.

Since you are a skyrim player, make sure you go through this page --> http://www.uesp.net/wiki/Differences_Between_Morrowind,_Oblivion,_and_Skyrim