Disco not starting

I have a problem with my 93 200tdi. After starting ok all day I went to start it tonight and nothing the starter wont turn I can hear the starter relay clicking but no starter. I also noticed the interior light electric windows clock and radio are working intermitantly. The clock lights up but no numbers displayed the radio has lost its memory and flashes on and off the interior light will sometimes come on but the windows have stopped working altogether. All this has just happened tonight as all was ok about two hours previous. Also the lights dont dim when the starter is tryed but the radio, int light and clock do then go out altogether. I am assuming all the problems are related as it all started at the same time. Any help is much appreciated
Thanks

Check your battery terminals, also your earth lead. check all your fuses - also that they are the correct rating and seated properlly.

Sounds like something is "loose" as oposed to "broken" to me!

TRY THIS
if the lights dont dim when trying to start, this indicates a fault in the circuit or solenoid.
like lezel69 said, the earth's a good place to start. clean the battery, engine and transmission earth points.

check for voltage at the positive lead connection to the solenoid. if all o.k, disconnect the wire from the solenoid blade terminal, check for live with the ignition in the start position, if circuit is live, everything's o.k. if not the fault's in the ignition/starter switch or wiring.

to check solenoid, test from the battery positive feed connection on the starter side of the solenoid and earth, turn ignition to the start postion you should get a reading, no reading, faulty solenoid. if everything checks out the fault could be in the starter motor.
if its not that, then, bugger if i now

Well had a good look today and eventually found what was wrong. Checked everything and found that there was no live feed to the starter relay. From the battery there are 2 thick brown wires that come from the positive terminal one goes to the glow plug relay and the other splits into several other brown wires and goes through the bulk head just above the servo. Looking from under the drivers footwell you can see the wires as they dissappear into the loom. So what I did to repair it was find one of the thick brown wires on the back of the fuse box and spliced and soldered a wire of the same thickness into it and ran the other end to the starter relay and did the same with the brown wire there and hey prest everything works again as it should. Obviesly there is a brocken wire behind the dash but as I am back feeding the circuit and all the brown wires come from the same source there should be no problem. The haynes manual is usless as it shows a fusible link, for 93 on nothing up to 93, which I cannot find unless it is behind the dash. Hope this is of help to anyone with the same problem.