Hello, i want to prevent anyone seeing my web browser or other software data on my Windows based PC.

I want peace of mind that no personal data can be obtained out of my system harddrive, so i think only answer to this is encryption of whole windows partition?

so how to encrypt it the best way while allowing easy and regular backups of this system drive/volume so i can restore it anytime on another new hard drive?

There are OS encryption options: http://internetlifeforum.com/security/2880-ways-achieve-full-disk-full-os-encryption-top-security/