Um, not successfully and not to any lasting effect. The US got them for various antitrust offences and ordered the company split apart but the order was dropped and MS never had to change their business practices.

The EU got them for illegal bundling of Windows Media Player, and they paid a fine which was tiny in comparison to the scope of their business. However, apart from releasing a non-WMP version of Vista through very limited channels at the same price as regular Vista (so that no one would buy it), their practices again did not change and anticompetitive bundling of WMP and IE continue de facto.

Their OEM deals, which in my opinion are the worst offence, were never investigated.

Their use of very-slightly-incompatible formats like MS Java and IE's rendering engine up until IE8 in order to lock out compatible programs were never investigated.

Their baseless patent threats against Linux companies which bullied many into damaging cross-license deals were never investigated.

Their deals with schools and government bodies to provide Windows and Office without a fair bidding process or a cost review first were never investigated.

Their illegal actions with regards to the "standardisation" of OOXML were never investigated. These included bribing officials who voted, blocking OOXML objections by interfering with the process, causing national bodies to go against the advice of their own technical committees were never investigated.

Their "Vista Capable" program that stated that certain Intel integrated graphics chips were sufficient to run Vista when they weren't, with internal e-mail evidence and whistleblower testimony confirming it, was brought to court and then dropped for no adequate reason.

I could go on...

Haha, that pic in the OP looks almost like some sort of new DS. :p It's so tiny, awwwwww!

There is nothing anti-trust about that.  It is simple customer segmentation, a basic marketing strategy.   

If it was MS to sell PC's segmenting OS according to these criteria, it would be normal, but MS doesn't sell PC's, it's imposing these criteria to PC producers it sells its OS to. This at least raises some doubts, it's like if I sold to a retailer basic nylon and luxury silk umbrellas and forced him to sell the basic ones only to people short, with a leg missing and poor clothes.

My girlfriend bought herself a new netbook a few months ago. She got the Asus Eee mainly because it came in pink, but also because it was cheap. She doesn't do much on the computer but maybe play a few games and check email and stuff like that. She got it for I think like $250. Now if you can get a regular laptop that cheap I would love to see it. It runs XP as she did not like the other ones that had Linux on them.

This. And the only reason the OEMs agree is Microsoft's dominant position in the PC market.

 That is an incorrect analogy.  MS isn't forcing anyone to do anything.   They are simply exercising control over the approved use of their products to protect their brand.   The customer elects, or not, to purchase the license.

MS is saying to the customer, netbook manufacturers, I will sell this specific version of an OS designed and priced for Netbooks.  However, as a condition of that sale only products meeting these characteristics are eligible for that price and feature set.  This prevents cannibalization of the full OS market on laptops.

You're assuming that netbook manufacturers have the choice to say "No". But they don't. If they said that, they would be charged full price (>$100 instead of $30) for Windows Vista instead and thus would go out of business in competition with those who accepted the deal. If they didn't offer any version of Windows then they wouldn't sell many netbooks because Windows is all the consumer knows due to the existing desktop monopoly.

So it's accept the deal or don't make netbooks profitably.

That's exactly the scenario a netbook is designed for - they will also do media playback perfecty well (file based, not DVD based) and have great battery life.  Atom based netbooks (which is most of them) run Win7 very nicely even in beta / build 7000.

Personally I have a "small notebook" that's not much bigger than a netbook (13 inch screen) but is far more powerful (since I use it for software development).  I never understood the desire for SUV sized "notebooks".