Mk2 gti 16v won't start!

[Marb]

Hi, first post here, sorry for starting with a please help me question.

Driving to work the over day, car started to kangaroo violently, I got it off the road and could hear the underside fuel pump droning, (there had been a strange noise for a while I had been ignoring) car then died and wouldn't start and I got someone from work to tow me home.
I replaced the lift pump thinking that might be starving the other pump causing the problem. Took the car for a 40min drive after and all was good, noticed there is a faint hum coming from the boot which I don't think I  used to have but was glad to get car running again.

Went to start the car 4 days later, it started then stalled straight away and now won't start. Pump makes normal priming noise on turning key, battery has plenty of charge, checked and I've got a decent amount of fuel going in at the engine when I turn the key, and there's a spark.

 Not sure where to look next, trying to avoid going to a garage and emptying my wallet!  Any pointers on where I should look would be greatly appreciated

[sparkplug]

if your getting a weird noise from the hatchback, are you sure it's not the pump inside the fuel tank
 playing up ?
mine did a similar trick when it died

check also the fuse panel, mine had melted taking out the fuel pump fuse, which I didn't initially sus was the pump going home & drawing to much current 

[Marb]

The pump in the tank is the one I've just replaced, although it does seem the likely culprit for the new humming noise. I noticed after that when the car did run that the drone from the underside pump has disappeared.
When I disconected the fuel pipe under the bonnet and cranked the engine I was getting a good flow of petrol coming out so not sure if it's a fuel pump but don't know what else it could be.  I'm just not sure what to do next..