First verse:

Great Mighty Poo:
Ahem-hem. Mi mi mi mi miiiii …
I am the Great Mighty Poo
and I'm going to throw my [bad word] at you.
huge supply of [bad word] from my chocolate starfish.
How about some scat, you little [bad word] 
Second verse:

Great Mighty Poo:
Do you really think you'll survive in here?
You don't seem to know which creek you're in.
Sweet corn is the only thing that makes it through my rear.
How d'you think I keep this lovely grin?
(Have some more caviar!)
Third verse:

Great Mighty Poo:
Now I'm really getting rather mad.
You're like a niggly tiggly [bad word] little tag-nut.
When I knock you out with all my bab,
I'm going to take your head and ram it up my butt!
Conker: Your butt?
Great Mighty Poo: My butt!
Conker: Your butt?!
Great Mighty Poo: That's right, my butt!
Conker: Err …!
Great Mighty Poo: My butt!
Conker: Agh!
Great Mighty Poo: My Buuuuuuuuutt!
Final quote:

Great Mighty Poo: Ah! You cursed squirrel! Look what you've done! I'm flushing! I'm flushing! Oh, what a world, what a world! Who'd have thought a good little squirrel like you could destroy my beautiful clagginess! Ah! I'm going! Oh! Ahh! No! Aaaaaaah!
Conker: Huh huh! Now that's what I call a bowel movement!