Dlink w/less - Computers not seeing each other

Hi, I'm hoping someone can shed some light on this it's driving me crazy. I
have a network with 4 computers.. two are wired, two are wireless. I'm
using a d-linkdi-624 wireless router for wan and lan.

My prob. is this:
The computers can all access the internet which is great, but the wired
computers do not see the wireless ones in network neighborhood... actually,
sometimes they will see them but won't let me access them.. it will say
something like "The computer did not receive your request. Try again
later". Two minutes later I will go into network neighborhood and the
wireless computers are not showing up at all again. Now, the wireless
computers can access the wired ones... open files, drag files over, etc.

This was all working ok up until the other day when I changed the status of
the newest computer's printer to enable sharing (it was originally set up
as a local printer).

Anyway, all settings seem to be correct as far as enabling sharing,
workgroup naming etc. Incidentally, 3 of the computers are using 98se and
the other one (one of the wireless, and the newest one) has ME.

Any help would be greatly appreciated.
Please, my sanity is at stake :-/

Thanks in advance,
Sailor