Considering WiFi-Currently Earthlink DSL

Bear with me, I'm really in the dark about WiFi so the wording of my questions may sound goofy. I have Earthlink DSL and am using a laptop running Windows Vista Home Premium, connected to the internet with a DSL modem. I contacted Earthink about getting WiFi and was told I'd need a WiFi router that would connect through my DSL modem.
Does anyone out there have Earthlink DSL with a WiFi router? Are you happy with it? I found some posts on another bulletin board and they were all extremely unhappy with Earthlink WiFi but it sounded as if they weren't connecting through a DSL modem.

I'm confused and perhaps what I'm asking doesn't make sense. Can anyone help me make a decision to go WiFi with Earthlink? I want to be able to take my laptop to the living room and connect wirelessly and also for my husband to connect with his laptop in his workshop. I should mention that I don't want to drop Earthlink as I really like it. A lot! But if their WiFi service is lousy then I'll just stick with my DSL for the time being.