Multiple access points to flood an area.

My attempts to provide reliable wireless access to guest laptop
computers over an area spanning about 100 feet have proved unsuccessful.
I suspect the problem is interference from numerous other wireless
devices in the area. A possible solution would be to position two
separate wireless routers (access points) toward the edges of the area
with each wireless router (access points) hardwire linked to the modem
via (possibly an Ethernet switch and) CAT5 cable.

My current wireless router / access point of choice is the D-Link
DI-524. It has been chosen because the native IP range 192.168.0.X of
the D-Link does not overlap the 192.168.1.X IP address range of the
router built into the 2WIRE2701 modem (wireless option disabled). My
guess is that I can either: (1) configure each D-Link wireless router so
they have non-overlapping IP address ranges and feed them in parallel
from a switch, or (2) disable the DHCP in one of the units, and feed it
(the second in the chain) from the first unit.

Will either of these schemes work? How do I best configure the D-Link
DI-524 devices so they act in parallel to flood the area with signal?

WindsurferLA