While the installer might be in English, the program itself includes a Russian translation.

To download and use in Russian ( rus ), follow these steps to ensure you get a safe, official version that supports your language. 1. Download & Installation

WinDirStat visualizes your storage so you can see what is "eating" your disk space. WinDirStat Portable | PortableApps.com

The most reliable source for the portable version is PortableApps.com .