Microsoft's monopolization practices have had a detrimental effect on the operating system market and in the computer industry in general, as you would come to expect from a monopoly like Microsoft. What needs to be done is it has to be broken up, if we are actually serious about fair competition and "free markets".
To argue that Microsoft is a monopoly is a totally mixed up argument, there was a time where it was close to being a monopoly, then the government got involved and all the antitrust lawsuit, which completely decimated the stock value.
If you look at Monopolies, today, Apple is closer to being a monopoly, in fact, probably even closer than Microsoft ever was, Google, also close to being a monopoly, Ebay likewise.
"Under the Sherman Act monopoly power is considered the ability of a business to control a price within its relevant product market or its geographic market or to exclude a competitor from doing business within its relevant product market or geographic market"
Look at that definition and put it into perspective, Apple with their IPOD, IPAD, and IPHONE I would say are dangerously close to fitting that definition,
No, Microsoft should not be broken up in to two or more companies as Microsoft does not hold a monopoly on the technological landscape today. It has several competitors such as Apple and Google who offer rivaling, and in some cases superior, products such that Microsoft does not come close to holding a Monopoly.