Networking laptop w/built-in wireless to USB adapter

Want to wirelessly network laptop (win xp, built-in wireless-b card) with desktop. Looking at an Airlink wireless-G USB adapter for desktop computer (win ME). Can I network using this simple solution, or do I need a router? Also, I assume I'd have to enable sharing for certain directories/files, but will I be able to use my dial-up connection on the desktop to remotely surf the web with the laptop?

 

The cheapest would be to get two Wireless cards, establish Wireless Ad-Hoc connection, and use windows ICS to share.

Instruction for Ad-Hoc will come with the Wireless cards.

ICS here: http://www.homenethelp.com/ics/ics-install-s98.asp

A more expensive solution would involve getting external Modem and A Wireless Router.

See option 3 here: Sharing the Internet with DialUp Connection.