I'm not an expert (sorry), but I would identify your bug as a mid instar of the Hawthorn Shieldbug - Acanthosoma haemorrhoidale, but I'm happy for a real expert to tell me otherwise. I have just spent quite a bit of the morning trying to identify various bugs myself (with mixed results!) so had the guides to hand!
Top one is a Green Shield Bug nymph, Palomena prasina: http://www.essexfieldclub.org.uk/portal/p/Your+Forum/r/view/s/200809.
Sorry this isn't exact but the second picture looks like some species of Squash Bug (considered a pest but I don't mind them), in fact I have seen that exact species in my garden but don't know the name either.
Hope this helps any expert trying to identify the little insect.