Problem with esp on VW Bora?

As with many VW owners posting on this site I have a problem with the esp on my VW.
I have a 10 yr old Bora (diesel tdi) and at first the esp light problem was intermittent and seemed to happen when the tyres hit a section of loose gravel on the road. The garage plugged it in to the computer and said there was no fault with the esp and suggested that it might be to do with uneven tyre wear or tyre pressure or the balancing being off. However, as of yesterday it is on permanantly even when the car hasn't yet moved. It's not just the light, but the abs is kicking in (if that's what it is - the car drives a little juddery especially in low revs and almost feels like the engine is misfiring)
I'm reading lots of reports about the esp light coming on but not about the way the car is behaving - do I have a different problem? At 10 years old the car isn't worth much more than the repair costs quoted by others on this site, so I'm very worried!