我該下載哪一版的windows 8 - Windows

我想要在我的筆電灌windows 8
我們學校可以下載免費的
我以為只有pro和非pro
結果我看了一下list發覺怎麼這麼多選擇…

Microsoft Windows 8 Debug/Checked Build 32-bit (English) - DreamSpark
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Microsoft Windows 8 Debug/Checked Build 64-bit (English) - DreamSpark
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Microsoft Windows 8 Professional 32-bit (English) - DreamSpark
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Microsoft Windows 8 Professional 32-bit (English-Great Britain) - DreamSpark
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Microsoft Windows 8 Professional 64-bit (English) - DreamSpark
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Microsoft Windows 8 Professional 64-bit (English-Great Britain) - DreamSpark
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Microsoft Windows 8 Symbols 32-bit (English) - DreamSpark
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Microsoft Windows 8 Symbols 64-bit (English) - DreamSpark
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Microsoft Windows 8 Symbols Debug/Checked Build 32-bit (English) - DreamSpark
Available to: Students/Faculty/Staff
Free
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Microsoft Windows 8 Symbols Debug/Checked Build 64-bit (English) - DreamSpark
Available to: Students/Faculty/Staff

先說一下我的筆電很怪
原本是vista 32 bit 4G Ram(只能讀到3G)
後來升級到windows 7 32 bit
可是因為一直發生問題，所以就拿回給宏碁升級成windows 7
結果沒想到它們直接灌windows 64bit
這讓我很困擾...32bit和64bit只是軟體的差異？
當然ram 是讀到4G了
可是用到%70電腦就會當...感覺可用的還是在3G左右
目前的話我裝的是windows 8 release preview 64 bit
那正式版的話我該下載哪一個呢？

話說我另外一台hP的筆電裝的是windows 7 home premium 64 bit
我看學校有professional 版的，就下載下來裝
結果裝了整個介面都跑掉快把我嚇死了
原版內建軟體也都不見了，防毒也不見了
到底windows 7 pro和home premium有什麼不同？值不值得升級呢？

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