Windows 32х и 64х чем отличаются(плюсы минусы)?

Архитектурой. Основное отличие х-64 винда может использовать более 4Гб оперативки, плюс одному процессу может выделяться более 2Гб той же оперативки. Минус - старые версии программ могут не работать. Если оперативки более 4Гб ставь 64, если менее 32, если 4Гб - все равно. По производительности разницы нет.

Плюсы и минусы.

Advantages of 64 bit OS

RAM Usage is high
Certain programs written for 64 bit computers can make better use of CPU and RAM, giving a LARGE performance boost (such as 64 bit Photoshop)
64 bit is becoming more and more common. As average RAM in a system increases, there will be no choice BUT a 64 bit system.
With 32-bit Windows, you can use a maximum of 4 GB of RAM, but in 64-bit Windows you can upgrade your RAM to 8 or 16 GB.
64-bit Windows is more secure than 32-bit windows. With 64-bit system you can advance security features like Kernel Patch Protection and many more.
64-bit can run many complex applications simultaneously. a 64-bit window is more suitable for applications like Photoshop, Video Editing, games, CAD etc.
In theoretically, A 32-bit Windows 7 can use max of 3.12 GB RAM. But 64-bit Windows 7 can use the full 4 GB RAM.
Disadvantages:
Many software and games are still not compatible with 64-bit of Windows
Needs a minimum of 2Gb of RAM to run
Needs a 64 bit processor (which is expensive than 32 bit processors) to run
If it runs in 32 bit processors then CPU usage may become 100 % often and system will start to hang
System uses more RAM to run the OS and programs