Almost everyone in my family and extended family has owned a pet snake at one point of another. Everything from Olive Pythons, Jungle Carpet Pythons, Childrens Pythons (my first snake! xD), and one Uncle has a permit and he keeps over 20 different snakes, both venomous and non-venomous.
They make excellent pets IMO. Never had any problems with them. Was only ever bitten by a snake once but that was at a zoo and the person who held the snake before me had stirred it up and it was scared so it bit my arm. I bit it's tail. It let go pretty quick.
Depending on where you plan on keeping it and whether you just want something pretty to look at or a snake you can actually handle should affect your decision. A good snake for a first time owner is the Childrens Python. They don't get very big, aren't particularly dangerous, and have one of the most even tempered natures of any snakes I have come into contact with.
Whatever snake you choose, make sure you get it young enough that it can still 'learn'. You want it to be able to recognise you just like any other pet. The more time you spend with it, the more it will come to realise you as a safe haven when (and if) you let it out of the tank.
As for getting your mum to like them, first, is it just snakes she doesn't like? Or reptiles in general?
Either way, find somewhere that has reptiles, and show her. Get her to touch one if you can. Most people don't like snakes because they think they are slimy. Once they get over that, they just worry about the head. And once they realise the head is soo not interested in them, they pretty much lose their fear and hatred of them. Most of the time. Didn't work on my nan. Give it a try though. Even if you just find some sort of lizard. I dunno where you are, but some petshops might have some, if not, try and find one around your house. My garden is littered with Blue Tongue Lizards and Geckos.
On a side note, I don't know if you have or not, but make sure you check out all of the proper procedures for getting your reptiles license. In that process it will tell you what types of snakes you can and can't own, and will give you ideas on what snakes in general are best for first time owners.
