Laptops don't stand up as well as desktops, either flat or tower. That being said I have a reconditioned ThinkPad that came with XP all for about $300 at MicroCenter. Close to having two years on it with out a spec of trouble. But I also still use the Pentium IIs once in a while, one with WIN98SE and the other with DOS 7, units I have had for over a decade now.

Be aware that there are better built business grade computers and there are home grade ones. For my money a used recent business grade unit is very likely to give a more solid performance for longe than a new home grade computer and cost a bunch less in the process and in many cases bundled with most of the software you will need.

You gotta go some to find a more consistently well built, durable computer than an IBM in the brand name units. And say what you want to I have yet to see a laptop as reliable from unit to unit as a ThinkPad.