how to configure my new server

I've a new configuration for our web server

Processor Processeur Intel Xeon 2.0 Ghz / 512 Ko de cache L2
Memoiry 1 Go DDR SDRAM
Disk1 18Go Ultra 3 (Ultra 160) SCSI 15 Ktpm
Disk2 18Go Hot Plug Ultra 3 (Ultra 160) SCSI 15 Ktpm
Disk3 18Go Hot Plug Ultra 3 (Ultra 160) SCSI 15 Ktpm
Disk4 18Go Hot Plug Ultra 3 (Ultra 160) SCSI 15 Ktpm
Disk5 36Go Hot Plug Ultra 3 (Ultra 160) SCSI 15 Ktpm

I will install a Mandrake 8.2

It's an application server that runs things other than just postgresql.
It also runs: apache + Php , bigbrother, log analyser.

At the moment, on my old server, there's postgresql 7.2.3
my database takes 469M and there are approximatively
5 millions query per day

what values should I use for

linux values:
kernel.shmmni = 4096
kernel.shmall = 32000000
kernel.shmmax = 256000000

postgresql values:
shared_buffers
max_fsm_relations
max_fsm_pages
wal_buffers
wal_files
sort_mem
vacuum_mem

any other advices are welcome

thanks in advance

---------------------
Philip johnson
01 64 86 83 00
http://www.atempo.com