Crossover is for connecting two computers DIRECTLY together without any other gear inbetween. Like a hub or a router. A UTP is for connecting to a hub or router or some other piece of equipment. At the Uni's you're connecting to the network through a hub so you need the standard cable. And for 25' you should not pay more than about 10 to 15 USD.
Oh and since you're going to be using thier network be ready for all kinds of restrictions on where you can go.