It's a tar archive, just use winrar or 7zip to extract the files.
This collection contains every game ever made for MSX, and an emulator.
MSX was the name of a standardized home computer architecture in the 1980s. It was a Microsoft-led attempt to create unified standards among hardware makers, conceived by one-time Microsoft Japan executive Kazuhiko Nishi. Despite Microsoft's involvement, MSX-based machines were seldom seen in the United States but were hugely popular in other markets. Eventually 5 million MSX-based units were sold world-wide.
Nishi proposed MSX as an attempt to create a single industry standard for home computers. Inspired by the success of VHS as a standard for video cassette recorders, many Japanese electronic manufacturers along with Goldstar, Philips and Spectravideo built and promoted MSX computers. Any piece of hardware or software with the MSX logo on it was compatible with MSX products of other manufacturers. In particular, the expansion cartridge form and function were part of the standard; any MSX expansion or game cartridge would work in any MSX computer.
Nishi's standard consisted primarily of several off-the-shelf parts; the main CPU was a 3.58 MHz Zilog Z80, the graphics chip a Texas Instruments TMS9918 with 16 KB (KiB) of dedicated VRAM, and the sound was provided by the AY-3-8910 chip manufactured by General Instrument (GI). These components alongside Microsoft's MSX BASIC made the MSX a competitive, though somewhat expensive home computer package. This design closely resembled the Spectravideo SV-328 home computer, but was not completely compatible with it. Spectravideo later launched a system, the SV-728 which did adhere to the MSX standard.
Before the appearance and great success of the Nintendo Famicom, MSX was the platform for which major Japanese game studios, such as Konami and Hudson Soft, produced their titles. The Metal Gear series was originally written for MSX hardware.