First there really is not one brand that is best. The best home theater or surround system would be custom designed using speakers and equipment that each manufacturer specializes in making. Most of the best speakers are designed by manufactures that only make speakers, and equipment manufactures that only make equipment.
When your talking the best, most people are not familiar with the best brands being made. They are only sold in high end audio video stores. The chain stores only carry mid fi equipment at best (98% of it is low end), and many of these stores have no clue how to properly design and install a home theater system.
There is allot to know when designing and installing a higher quality system. The best place to go is your local independent high end audio video store. They not only carry the better brands of speakers and equipment, they generally have many years experience designing higher quality systems. Designing a system that is right for your needs takes someone with the knowledge and expertise to take the time and help you.
Unfortunately there is a tremendous amount of poor and even bad information on this subject and everyone seems to be an expert. Even some of the bigger trade magazines and online forums really don't know what they are doing. Absolute Sound and Stereophile are the two best trade magazines on the market, the reviewers are very knowledgeable, they do a good job of reviewing some of the very best in all budget ranges.
So when you say the best, it can get very expensive, the key is finding the best at your budget and if your able to invest a decent amount of money, leave it to a professional that knows what he is doing.
Kevin
40 years high end audio video specialist