Engine earth strap is a classic failure point that gives conditions you describe. Of course ensure the battery is fine first, simplest way to do this, even if you have charged it and have a no start, is to pop a slave battery alongside it....this is easiest done with jump start cables and another car. If it starts your battery is suspect, if it still shows the same symptoms its time to look elsewhere. The next step is to use just one side of the jump cables and connect one clip to the battery earth (-) terminal and the other to a good clean connection on the engine, the bell housing bolt area is favourite. If the car now starts you have just about confirmed you need a new or cleaner earth strap. Simplest way to do this is pop another one on, you cant have too many earths!
Good luck, and please let us know how you got on.
