What kind of question is it? Almost like "What Vauxahal car is the best?" Thay all do well, so it depends what you ant to use it for sebus
Depends on what you use it for and everything.... And thats like sayin whats the best Operating System out there or Whats the best Browser etc...... Your going to have to be more specific because theres Windows Server 2008 R2 and Linux.... And thats not even counting all the editions of them cause Windows Server has Enterprise, Ulimate, Bussiness,etc And Linux has Redhat, Ubuntu, Kubuntu, etc..... Try being more specfic plz...
Quite a general question there.. Are you buying or just looking for knowledge? If buying you should state intended use, budget, preferred operating system (eg windows or linux offerings) etc.
A little late answer here but anyway: If we're talking Windows Server releases then I've got some experience in this area. Depending on what kind of rig you've got speed and accuracy is like day and night. On old hardware Windows Server 2003 with R2 loaded and SP2 loaded (either edition) is like a unstoppable beast, with that said you get everything here + you can actually make it to be and act more like an Windows XP machine. I wouldn't install Windows Server 2008 or R2 on older hardware, they're best suited for newer better hardware though Windows Server 2008 comes a little in the middle here but it's great once loaded with SP2. One thing to keep in mind is that Server 2003 and Server 2008 can be bought either as x86 or x64 where 2008 R2 is x64 only. But Windows Server 2008 R2 is like the king of the Server releases, it's x64 and it has everything you could want from it. I used it recently on a newer rig and boy did it fly and with a few tuning and tweaks you couldn't tell later if it was Server or Windows 7. Server releases is great for using as Workstation OS, they are robust, fast and pretty much unstoppable. The only downside as I see is that there isn't any free antivirus for it. So to answer your question, it totally depends on what hardware you should use it on and what you should use it for, but all Windows Server releases is pure beasts in terms of speed and accuracy.