OSPF basics

I am new to ospf and routing protocols... All the howto's and stuff I
could find so far describe pretty complex samples, so I'm asking for
some feedback or perhaps fine manual urls


Some ASCII fixed width art:

| and - is LAN/Ethernet
= and " is Serial/Wan (T1)

core subnet 10.1.1.0/24
|
|--s102--Local Subnets 192.168.1.0/24
|
|--s101--Local Subnets 192.168.2.0/24
|
|--r100
"
" p2p 10.5.1.0/30
"
|---r1
|
|---s2--Local subnets 192.168.5.0/24
|
|---s1--Local SUbnets 192.168.6.0/24
|
|
| The stuff on this branch does not run ospf
|---isa2---fw1---r2====isp/internet
| |
| dmz's
|
core subnet 10.1.2.0/24


Not that the brand may matter but anyway, the equipment list;
OSPF Enabled items:
s102 Nortel Passport 1424T (L3 sw)
s101 Dell 6024 (L3 sw)
r100 Cisco 1600
r1 Cisco 1600
s2 Nortel Passport 1424T (L3 sw)
s1 Dell 6024 (L3 sw)

Static items:
isa1 Microsoft ISA Server (proxy/fw)
fw1 perimiter firewall
r2 Cisco 2600

Scenario:
Two core-lan's connected by a p2p WAN with r1/r100.
OSPF Enabled and using a single area, 0.0.0.0
On the Nortel switches I simply enabled OSPF and the core interface.
On the Dell switches I added area 0 and enabled the core interface.
On the two cisco routers r1 and r100 i did
router ospf 1
network 10.0.0.0 0.255.255.255 area 0
network 192.168.0.0 0.0.255.255 area 0
on both of them, If I understand it right it will now advertise
all 10/8 and 192.168/16 on all (both) interfaces?
Everybody does see their neighbours in ospf status.

Issue 1:
Routes from the subnets of s101 and s102 does not get added
to the routing tables of s1, but they do get added to s2.
(And r1 holds them all just fine as well)...
In the "OSPF Link State Table" of s1 I see the entries for these
routes, but they do not get added to the switch routing table...

Issue 2, perhaps related:
Subnets connected to S2 does not get picked up by neither r1 or s1


I guess my initial question here is if I am doing something
fundamentally wrong?
As for right now to get by I add some static routes and turn on
advertisement of static routes in the Dell

switches.
Should I use two areas?

Any comments appreciated.