Need Help in Vlan Routing

Hi all

I am new to this forum

i am having some doubt in Cisco Vlan Routing Please help me to Solve this problem....

i have Cisco 4700 Switch
In that Switch i have created more than 6 Vlan and with 6 Peplink connection
and i enable DHCP from the Core Switch.
the problem is in DHCP is giving ip : 192.168.1.14 Default Gateway : 192.168.1.1
intervlan routing is working perfectly between 6 vlan but internet is not working
if i change in DHCP Configuration to give 192.168.1.14 Default Gateway : 192.168.1.10(peplink Ip Address) internet is working perfectly but intervlan routing is not working.....
i know there is a routing option in peplink Device we can use it for routing but routing is seems very slow (may be because peplink interface speed is just 100 MB)
please help me guys to solve this issue............

i need intervlan routing should work from the core switch...
and internet operation it should navigate to the peplink Device for internet...

jeevachandran