I've been away (at DLR Paris) so not been checking in here for a few days. Thought i'd give you all some of my DLRP travel tips.
From barcelona to Paris will be quickest by plane, but by train may be more confortable/less rushed. In Europe we have a lot of budget airlines that are cheap for your basic seat but charge excessively for checked luggage (hold luggage) and the convenience of checking in at the airport. Some of them also severly limit the weight/size of hand-luggage. If i have checked luggage i personally avoid the budget airlines.
As an example, i just flew Air France to paris from the UK - cost us £220 including drink and snack on plane, 20kg checked baggage per person. The equivalent flight on a budget airline (similar times of day/same airport) would have cost us £250 including the hold bagage and with no drink/snack. (luggage was going to cost us £50 and only 18kg per person).
There is a train station at DLR Paris itself, so you can get the Eurostar from London direct to DLRP, or get an RER train (line A) from central paris out to DLRP. RER trains from Paris are about every 10-15 mins and take around 45 mins from central paris (depending on your stop). Info on Paris region trains can be found at
www.ratp.fr (there is an english option).
If you're flying into Paris there is a bus service that costs around 18Euro per person each way.
www.vea.fr If there's 3 or more of you for just a couple of days it may be cheaper to hire a car (assuming you're happy to drive a manual).
For DLRP tickets - if you're staying 3 days or more, it'll be cheaper to buy the fantasy level annual pass. Avoid the Francilien as this has odd exclusions (can't visit on the 2 days after you buy it). You can buy these on the gate as a walk up and then have the paper ticket converted into a plastic card at the annual passport office. The AP's carry some discounts on food and in the shops.
If you're staying onsite - the website only alows booking of ticket-inclusive packages, but if you call the phone lines you can book room only. Expedia often has room only too. There are some offsite hotels that are pretty close and are usually cheaper, and some have shuttle buses. Check expedia or equivalent for these.
I'd highly recommend splashing out on seeing Buffalo bill wild west show (dinner and a show - great fun for the whole family and not something Disney have really done at their other parks)
As there are 2 parks i'd recommend 2 days (though you may only need 1/2 or 2/3 of a day in the Studios as there's less to do there)
For those of you used to DL and WDW, DLRP is similar but different. The standards of customer service are not as high and the park is generally not in as good state of repair as in the US. However, this doesn't detract too much from the experience and imho DLRP does offer the best versions of Haunted Mansion and Pirates.
If anyone has questions, i'm happy to answer, and there's always the DLRP board here on DIS.
You just about figured it out! Here's a little more clarification: 
We'll also be celebrating appleguy's birthday (his is May 13 which will probably end up being a travel day for us so we'll celebrate when we get on the ship!!) 
)
