For FireRed:
If you want to skip the intro: [0x080EC5D0]=0x08078915.
If you want to skip the intro+titlescreen: [0x080EC5D0]=0x0800C301.
If you want to skip the tutorial+oak:
- [0x0800C4C4]=0x08056645
- [0x08054A68]=0x4C3C
- [0x08054A6A]=0x6820
- [0x08054A6C]=0x4900
- [0x08054A6E]=0xE001
- [0x08054A70]=name of the player
- [0x08054A7E]=0x4E34
- [0x08054B3A]=0x0000
- [0x08054B3C]=0x0000
pls credit
EDIT:
If you want to skip the intro+titlescreen:
- [0x080EC5D0]=0x08079255
- [0x080EC5C6]=0xB431
- [0x080EC5C8]=0x4700