I don't know of any router that can use a dial-up line - not enough bandwidth to share there
If he wants to share now before getting ADSL, I would suggest an ADSL Wireless router (Linksys
) but using ICS to bridge the modem connection on the PC with the Lan card. eg PC connects to Dial-up, RJ45 from PC to Router, Wireless from Router to Laptop, Router has no ADSL atm.
That way, when he gets ADSL he can just plug in the splitter and ditch the modem.
HTH