can't ping desktop from laptop

ok, so i can't ping the desktop from the laptop over home wireless network. also can't share the desktop printer, but can see it on laptop. i know they're related. i can access internet wirelessly fine from laptop. router is linksys wrt54g. i can ping laptop from desktop. i can ping router from laptop. desktop has zone alarm, laptop ip is in trusted zone. laptop has windows firewall enabled now, but tried sharing and pinging with firewall disabled without success. i could try a print server but get the feeling it wouldn't work until i get this resolved. suggestions anyone?

xp sp3 of course. what else would be giving me such problems!