I would avoid Dell. We have had problems with 2 Dell laptops in the family.
We have had a trouble free Compaq/HP for 3 years. Also I would look at Lenovo as these where formally IBM and we have an IBM T41 Thinkpad giving good service, and a nice compact machine.
As much as the spec of the machine, pick it up and feel the weight and balance and look at the quality of the case etc.
Regarding memory, go 2GB RAM minimum. There are still machines offering 1GB RAM but I would avoid these, you want to future proof as much as you can and it will probably only be €50 more or so to get up to a better spec. Less important is disk space but minimum would me 160GB but 250GB more the norm these days. Is easier for non techy to add more disk storage than upgrade the RAM later.