Latency in Internet connections from Europe to USA

Solution 1:

Anywhere in north-western Europe (.nl, .de, .uk, etc) will give you perfectly good performance.

Moving traffic across the Atlantic and back will add ~90ms minimum latency to a link, and latency can affect absolutely maximum bandwidth because of the TCP window.

I'm in Amsterdam at the moment, though, and latency back to the UK is only 11ms.

Solution 2:

Good thing about the Netherlands, is that that AMX-IX, world's largest IXP is located in Amsterdam. So that's less hops, your packets have to do.

As for impact on the site, that depends how interactive it is. Latency has negative impact on gaming and such, but has no impact on classic HTTP. For classic web what's important, is the bandwidth.
On bandwidth vs latency (wiki)

BTW. OVH.nl might be an option for you. But don't let .nl domain fool you. They are French company, have data centers in France (Roubaix and Paris).