Installing service as Admin

I need to install service on vista with all the privileges as it gets when it
runs as localsystem on XP. When I install on Vista, the service is unable to
call OpenProcess successfully for the processes that run under different user
account.

I tried changing privileges with ChangeServiceConfig2 but after running it,
it not only does not work, I am also not able to uninstall service.

servicePrivileges.pmszRequiredPrivileges =
(L"SeTakeOwnershipPrivilege\0"
L"SeAssignPrimaryTokenPrivilege\0"
L"SeImpersonatePrivilege\0"
L"SeCreateGlobalPrivilege\0");

BOOL fRet = ChangeServiceConfig2(
hService,
SERVICE_CONFIG_REQUIRED_PRIVILEGES_INFO,
&servicePrivileges);

Can someone tell me how can I install service that can get all the rights
since I need to monitor processes running in other user's space.

Thanks,

P