The PAL version has a notorious "Menu Lag" when using the "Development" (MS Design) screen. To fix this in PCSX2:
The gameplay loop is very deep and rewarding. You start each mission with a base ship. You deploy your mobile suits onto a grid. You move your units to engage the enemy. Combat triggers a 2D animated battle scene. These scenes look great for the PS2 era. They capture the feel of the TV show. Winning battles earns you experience points and capital. Sd Gundam G Generation Seed Iso Ps2 Pal
For an English speaker, playing the PAL ISO is the definitive way to experience the Cosmic Era story through the tactical lens of G Gen. The PAL version has a notorious "Menu Lag"