1. Yes, with a lot of experience, time, effort, and servers.
2. The graphics are good if a lot of time is put into the graphics

. Then if a lot of time is put into the game code regarding the graphics, the game can look good. The graphics are only limited by what you put into it, so there is no real comparison.
3. Yes and no. I haven't used pro much, but there are differences. If you just want a hobby language and don't want to spend a lot of money, go classic, it is still powerful. Pro is more powerful and versatile, but it depends on what you need it for.
From your questions, I assume you plan on making an mmorpg on par with wow, guild wars, and runescape. Not to burst your bubble, but seriously, DON'T for your first project. You won't be able to do it, no one can. Start simple. I am sure that others will join in to reiterate this point.
Ever notice how in Microsoft word, the word "microsoft" is auto corrected to be "Microsoft" but "macintosh" just gets the dumb red underline?