请教加州老李关于 Vista 安装盘

There are 12 parts in 432329 section. Are they same? I downloaded first one. I installed, erased and reinstalled again. The different product ID can be viewed, each time. Do not know why? Could I active it? If so, will it conflict with some one else with 432329.ISO or same product ID? If not, could I still use it after 30 days or would I lost same functions? I saw "only 240 days" some where. What is SHA1 and ISO/CRC? I tried to active it but get some likes " KMS host could not be located"