Can I use 2uF or 10uF capacitor instead of a 1uF with the LP2951 voltage regulator?
Yes, you can use a bigger capacitor on the regulator input (and typically anywhere that they're used to smooth out supply voltage spikes or ripples). And you can use regulators rated for higher currents; that's the maximum it's capable of but it won't push in more current than what the circuit consumes.