Luca, if you and your brother are comfortable providing tech support, go for the hackintosh. Not sure what your relationship is with your mother, but if it's a good one, you won't be dreading the out-of-the-air-help-her-troubleshoot- a-problem- on-a-friday-night scenario than if you can barely stand her. Also gives you an excuse to spend some quality time with her AND a cool machine
A little off topic, but I'm just wondering: is building a desktop hackintosh easier to do compared to building a netbook hackintosh? I know the Dell Mini hackintosh community is very active in making the hackintoshing experience as easy as possible.