Land Rover Repair: BRAKE PEDAL HARDNESS & Head Lamps, land rover discovery, xenon lamps

Question
I have a brake pedal hardness problem of my Land Rover Discovery Yr 2000 ENGINE No: 10P64436AG CHASSIS No: SALLTGM97YA264505 Manual Gears RHD
When I bring the car to a halt on a slope or in the city ( due to say a traffic jam), the gear is engaged in 1st gear and I keep the clutch pedal pressed along with the brake pedal ( as & when necessary). Now when the traffic ahead moves at a very slow pace ( as what happens in a traffic jam), we keep the clutch depressed and release ONLY the brake pedal ( in a slope) or (slightly depress the accelerator), at which the vehicle crawls forward. After two successive stop and go procedures, if we are still forced to crawl and repeat subsequent stop and go procedures, the BRAKE pedal becomes ROCK hard, and does NOT depress further, or you have to literally use all force in your  foot to stop the car. BUT after a gap of say 30 secs or so ( without pressing the brake pedal ), the brake pedal becomes normally soft and the brakes do take hold. This time gap of 30 secs MAY NOT be possible in BUMPER to BUMPER traffic whether we are in a slope ( which is worse) or in a city road in a traffic jam. So what could be the defect of the brakes and what is the solution?

Also the present head lamps have a rating of 65/55w ( for city driving), which is insufficient here in India where I live. I BADLY require powerful lights (Either halogen, or LED, or XENON lamps). Could you suggest the gadgetry required to safely fit these WITHOUT blowing the existing fuses? OR just a plain 100W Halogen lamp bulb in replacement of the existing ones?

Answer
You did not say if you have gas or diesel engine.  The brakes are boosted by vacuum, and the problem you describe is almost certainly a loss of that vacuum boost.  In the gas engine the vacuum comes from a tap on the intake manifold.  On the diesel it comes from a pump.  The vacuum source or the pump is almost certainly the source of your trouble.

As to lamps . . . you can buy higher power lamps but you need to fit ceramic sockets to take the heat, and you need to add relays and wiring to the alternator to avoid melting the turn signal/dimmer switch.