For the OP, I'd download Wefi, it's an app that looks for open networks and connects to the best one, also connects to any you have saved, much friendlier interface than the standard wifi settings, but I don't get why a speed test on my phone only gets to 5.5 mbps and on my wifi connected laptop it gets to 20.
Several reasons possible:
1) not the same speed test site.
2) buffers in the wireless for Droid not as good at throughput as the PC
3) Droid signal level may not be as strong as PC