My experiences with laptops (when working in PC repairs) are that the best brands in terms of quality are Lenovo, Sony, HP (business machines only, and some of the 5xx) and Fujitsu Siemens. Acer, Dell (particularly their home user orientated pap), Medion, Advent etc. are among the worst in my experience. I've posted this before, but the Acer build quality on most of the off-the-shelf high st machines is appaling, and their warranty and support is the worst I've ever used. That said, some of their machines are OK, and you usually get quite a good spec for the money. Toshiba Satellite Pro (and only the Pro!) are half decent, as are their Tecra range, but again, the high st stuff is lacking in quality.
Now if I were to buy myself a laptop, it'd be a Lenovo or Sony, depending on what I'd be using it for. For work, the Lenovo Thinkpads win hands down, though for home, the Vaio range would have something perfect I'm sure.