Windows 7 or 8?

Solution
You could get Win7 for a 64-bit system and update it to 8+ eventually-that may possibly be the cheapest way to do it. The older the operating system is, the less support it will have in time, but I think 7 has a few years left. 8 boots up quicker, but aside from that, it is not very different.
8.1 is just windows 7 underneath, optimised with touchscreen support and a start screen, and aimed at the home market. There are arguments in that 8 is faster for gaming, but tests from differing websites show that it can vary. There is no straight answer.
The main issues some people have with 8.1 with games seem to be related to driver support for their hardware, but compatibility with 8 and 8.1 is still very good with games that run on 7. If...
What games are you considering the most?

Unfortunately capability will always diminish as you move over to a new OS, but aside from that blue start screen I have found 7 and 8.0 to be very similar, and there do not seem to be many compatibility issues. If something works in the latest 7, there is a high probability that it will work in 8.0. Windows 8.1 on the otherhand, will likely decrease that likelyhood if you decide to update to it (Im using 7 and 8.0). This seems to be where most people are having issues.

If a game is very popular then there will likely be patches or updates for it to work on the latest operating system.
Most online stores now release games to be compatible with 7, 8 and 8.1. Stores such as gog release old and modern games and patch them to work on all OS. Every game I have on 7 works in 8.0, but they are recent and mainly online releases. From my experience, physical games on cd and dvd from big name companies such as EA, seem to be the most awkward when it comes down to compatibility for some reason (eg almost every game of theirs I had on xp never worked on vista or 7) but there will always be unofficial patches to use at your own risk, and windows 7 compatibility mode, as a last resort. The oldest software I have on the pc that still runs in 8 is unreal tournament 1999 and MS Office 2003.
 


i will be playing mmo's indie games and fps so if i get 8 it will be 8.1 so i should get 7?
 
You could get Win7 for a 64-bit system and update it to 8+ eventually-that may possibly be the cheapest way to do it. The older the operating system is, the less support it will have in time, but I think 7 has a few years left. 8 boots up quicker, but aside from that, it is not very different.
8.1 is just windows 7 underneath, optimised with touchscreen support and a start screen, and aimed at the home market. There are arguments in that 8 is faster for gaming, but tests from differing websites show that it can vary. There is no straight answer.
The main issues some people have with 8.1 with games seem to be related to driver support for their hardware, but compatibility with 8 and 8.1 is still very good with games that run on 7. If you don't want to use 8 apps shown on the blue metro screen (think of them as 'full screen gadgets') then you don't have to. You can stick to using the desktop and you are not missing out. If you want a start menu in 8, you can install classic shell or start8.

Modern games from now on should be set to work with 8.1. Most simple indie games should run fine if they worked on 7 and 8, and if any popular mmo's have problems, they will be updated to work on 8.1 and beyond so that they dont lose custom. Every pc nowadays is being sold with 8. Much software will eventually make the switch to being for 64-bit only, such as photoshop.

If you are not sure if an old game will run, check their official website forum or google 'does X work on 8.1' to find out if someone is running it ok. There will always be people with problems when you google that kind of question, but it will at least give an idea of what the worst possibility could be. For old FPS games, online shopping is your best bet - many old FPS games will be set to run on 8.1. gog and steam have FPS games such as far cry 2, medal of honor etc that have been tweaked to work fine on 7,8 and 8.1
 
Solution


http://www.hardocp.com/article/2013/11/24/battlefield_4_windows_7_vs_81_performance_review/1#.UpqHoOLddOI

I found that, at least with BF4 and BF3, Win 8.1 ran faster than 7 as the above article indicates. Win 8 just seems to flow smoother from a more subjective viewpoint, particularly after the latest updates.

Edit: scratch that. I just noticed the OP was not for BF3/BF4