Goku walks frustratingly slow in the first game. Use your emulator’s Fast-Forward button (usually the Spacebar on PC, or a hotkey on mobile). Set the speed to 150%-200% for over-world travel, then toggle it off for battles.
Once you learn Solar Flare (from Krillin or by leveling up), use it constantly. It stuns every non-boss enemy for 5 seconds, allowing you to punch them to death without taking return damage. Download Dragon Ball Z- The Legacy of Goku
When you level up, you get 5 points to allocate among Fighting, Energy, and Stamina. Ignore Energy for the first 10 levels. Put everything into Fighting. This directly increases your physical damage, which is how you kill 90% of enemies. Goku walks frustratingly slow in the first game