Are you looking to or convert your own existing ISOs?
To help you get your library started, I can provide more specific advice if you tell me:
When searching for a "full" set, it is important to understand the scale. A complete, uncompressed PS2 library (US, EU, and JP) can exceed 10 terabytes. However, a curated "Full US Set" in CHD format typically fits within 2 to 3 terabytes. Where to Look ps2 chd roms full
On average, PS2 games compressed to CHD are 30% to 60% smaller than their ISO counterparts.
Are you targeting a (USA, Europe, Japan) or a "Best Of" list? Are you looking to or convert your own existing ISOs
The LRPS2 and Play! cores both handle CHD efficiently.
Major emulators like PCSX2 and mobile options like NetherSX2 support CHD natively. You don't need to decompress the game to play it. How to Convert ISO to CHD However, a curated "Full US Set" in CHD
What are you planning to play these on (PC, Steam Deck, Android)?
Unlike older formats like ISO or BIN/CUE, CHD files are designed to be read directly by emulators. They compress the "empty" space often found on game discs, resulting in significant file size reductions while maintaining a 1:1 digital copy of the original data. Why Use CHD for PS2 Games?
A common misconception is that compressed files lead to "stuttering" or longer load times. Because CHD uses a "Hunk" based system, the emulator only decompresses the specific part of the disc it needs to read at that exact moment.