I have two friends who also don't get sick, which most likely means they have a hyperactive enzyme aldehyde dehydrogenase. Sadly that is a prime factor in determening wether people will become alcoholics or not.
Basicly the pathway is Ethanol -> Acetaldehyde -> Acetic acid, where Acetaldehyde is the most poisonous part of the pathway.
Aldehyde dehydrogenase does the last part of the pathway, namely Acetaldehyde -> Acetic acid. Alcohol dehydrogenase does the first part Ethanol -> Acetaldehyde. Each step is an oxidation.
Methanol undergoes the same oxidation with the same two enzymes. Methanol is very dangerous, 4 grammes is enough to end us, less can make us blind. It is not methanol itself that does it but the next oxidation step, into formaldehyde which is VERY dangerous as it binds to tissue and thus "destroys" it.
Methanol is exists in the range of around 4-35 grammes/litre in spirits, vodka with the lowest and cognac and whisk(e)y with the highest, it's part of the taste.
The reason we don't die from drinking spirits with methanol in them is that ethanol out competes methanol for the active site (where the oxidation happens) on aldehyde dehydrogenase which means we don't get as much formadehyde in our blood/organs. However it is still toxic so that is why people without hyperactive aldehyde dehydrogenase get headaches (primarely, the other reason being dehydration of the brain, so drink lots of water before you go to bed).