When Moeller High School decided to go with laptops for every student, they signed a contract with Dell. The next year IBM undercut the Dell price and the school foolishly went with them. Result one: two parts lists. result two: More down time/ repairs with the IBM's than with the two year old Dells.
I've had two Dell laptops and two Dell PCs over an 8 year span and they have been reliable machines. Most of my problems have come from bad software... bless you Bill Gates... rather than hardware.
That being said, Dell outsourced their customer service a few years ago and I've ended up talking to people who sound a lot like my old calculus prof. I didn't understand a damn thing he said either.
The techie at Hamilton County Education Service Center swears by a firm out of Dayton that builds your computer one at a time. They do all the computers, including repairing and reconfiguring the myriad kinds of computers you find in a county wide system that also serves private schools. Sorry I don't have the name but if your interested I could find out.