Windows 7 Should i and can i upgrade to windows 8

Minimum requirements from from MS:

• Processor: 1 gigahertz (GHz) or faster
• RAM: 1 gigabyte (GB) (32-bit) or 2 GB (64-bit)
• Hard disk space: 16 GB (32-bit) or 20 GB (64-bit)
• Graphics card: Microsoft DirectX 9 graphics device with WDDM driver

Additional requirements to use certain features:

• To use touch, you need a tablet or a monitor that supports multitouch.
• To access the Windows Store and to download and run apps, you need an active Internet connection and a screen resolution of at least 1024 x 768.
• To snap apps, you need a screen resolution of at least 1366 x 768.

Before proceeding I would consider the following:

1. Use something like Acronis True Image to make a complete image of your existing system to enable simple and full recovery. (you can get a fully working trial download).
2. Installing Windows 8 as a dual boot to enable use of either system.

I would always now go for 64 bit installation where supported.