I guess I could cycle to Paris and work my way to Northern Italy, I guess one fear is that i cycle into some heavy duty mountainous areas that either require a lot of pushing for days or a huge detour.
If you cycle from Paris to Northern Italy then that's exactly what's going to happen! It's very mountainous in the centre and, unless you go a very long way round, you'll have some real lung busters to cross.
For a first cycle tour, I'd tout for France any day. Obviously I'm biased because I live here, but the country offers so much for the cyclist. The variety of scenery is staggering, there are some beautiful villages, the food is marvellous and cyclists are given more respect by motorists than any other road user. In fact, I'd say that France is more suited for a first cycle tour than the UK, which for me is not an ideal touring country (too busy, too much agression directed at cyclists.)
I second what others have said about a route through. Avoid Nord Pas de Calais. It's an area renowned for friendliness, but the landscape is really monotonous with huge, flat fields with hardly anything to break up the view (or the wind). Normandy is very hilly in places, but it's no worse than the Cotswolds. The main problem with Britanny is the weather! Expect lots of rain - but you may find that you'd prefer to spend your time sampling the delicious local produce instead. If you want to go to Paris, take my advice and follow the Route Verte already indicated. For God's sake don't even considering entering Paris from the North. It's an urban maze and very hard to navigate around - you may even end up accidentally on a motorway. If you do enter Paris, don't expect it to be
quick in, quick out. Paris is the second biggest metropolis in the EU, only slightly smaller than London, and it takes forever to cycle through it even if you do know where you're going.
Whatever you decide, good luck!