The starting trouble sounds like a bad battery. Look up how to check the date code on a battery. If it's over 3 years old, you probably need a new one.
If the battery is new, it could also be that it's not getting a full charge. Check the connections at the battery posts and make sure they are tight.
You can also drive it to an auto parts store and they can test the battery and alternator for you, usually for free.