My TV is a Sharp 37 inch tv, it is about 2 years old, all of a suddent it will not turn on, the green power light is on but when i press the power button nothing happens.

Www.hdtvreview.com/pdf/sharp-lc-42d62u-manual.pdf
Above is a user manual, below, is a Service na repair manual. This is what the repair engineers use to troubleshoot and repair.
http://elektrotanya.com/sharp_lc-42d62u_lc-62c42u.pdf/download.html

Factory Default Reset:

- Unplug the TV and count to 10 slowly.
- Hold down the power button on the TV (not the remote.)
- Plug in the TV while holding power button.
- Count to 10 and release the power button.
- Turn it on and hope for the best.

it is nearly always my professional opinion that one should always get a "Quote" from the manufacturers recommended service center, I cannot stress how important that last point is. It is even worth the cost of shipping. you see an authorised service agent, will have trained staff, trained on their brand, also they have first hand access to parts, original parts. This will actually save you money and ensure you can actually get it back fixed. Of course asking for a "Quote" also gives on the option of repair or replace. Often my clients,do not go through with repair, unless it is moderate, but in some of the more costly jobs they see it, as do i, that a replacement, with a warranty, is a better option. As an aside here, one could then tear the TV down, and sell the Known Good bits. You'd be surprised who needs parts, i myself often must by from third party sources to effect a repair. So money could be recouped, somewhat,and help out someone else