I am setting Up a Cybercafe and i need help on Configuring Network Setup.

I have the following :

2 DSL Modem (2 Diff ISP's) 128kb/s
2 SMC 100base Switcher (20ports)
2 Netgear Internet Router(1 WAN ->4 Port LAN)
30 Windows XP PC - usage Chat/IM/Online Gaming/LAN Counterstrike
1 Spare PC (Can be use as a server)

Please advise on how to design best Network Solution. Preferably i want Linux/windows box as a Load Balancing/Gateway/Proxy Server which ever is suited with the recomended setup.

Thanks Guys..your help is much appreciated!

The split routing (two external routes) is handled by iproute2

have a read of http://tldp.org/HOWTO/Adv-Routing-HOWTO/lartc.rpdb.html Chapters 4

The bandwidth control is a bit more complicated..
There are quite a few options but all are quite complicated to set up.
cbq seems to be frequently used along with htb