felicia - oil and timing chain

hello,

a couple of questions...

1. i have an oil leak (there's a couple of patches on the road under the car about the size of cadbury giant buttons) in my felicia 2000w (mpi). it's taken about 500ml of top up oil in about 5000 miles (1 year), so is this anything i really need to worry about, as long as i am keeping an eye on the level?

2. timing chain. i'm at about 63k miles. eventually it will need replacing, and it's pretty rattly. the guy at the garage said doing it about 100k would be okay though. is there an indicator that it really needs changing? is wear on it something they would pick up in a thorough service?

thank you!