Bryant - you're largely right. Although ideologically very distant, there's not nearly as much difference in practice between 'New Labour' and the Conservatives as there is between either of them and the Lib Dems. (Old Labour would have been a different matter.)
A few that spring to mind though...
On the economy - specifically, on dealing with the deficit - Labour want to increase public spending over the coming year because they believe it's important to "sustain the recovery" before beginning cuts the year after. Conservatives say tackling the deficit is more urgent and needs to be done right away. I suppose that reflects a classic economic division.
On immigration, there's not nearly as much between these two parties as their respective rhetoric would suggest. The Conservatives are more keen on imposing a cap, and bringing it down to 1990s levels, but that's about it. They talk tougher but they're a looong way from Arizona! And countless Labour Home Secretaries have gone out of their way to out-toughtalk the Conservatives.
Probably civil liberties is a key issue that separates Labour and Tory significantly. The Conservatives, to their credit (IMO) want to scrap the proposed ID cards system, which Labour have pressed for. However the Tories also want to repeal the Human Rights Act. I might be won around to that idea if I knew more about what they propose for the British equivalent.
The Conservatives may be - in some respects - slightly to the left of your Democrats. They have been at pains to assure us about how committed they are to tackling environmental issues, global warming, gay rights, child poverty, and so on, even if details sometimes arise to make us question this.
Both parties are committed to the National Health Service. Both
claim to be committed to the future of the (licence-fee funded) BBC - though personally I don't trust that in Conservative hands.
But you're right, the Lib Dems are the most radical (relatively speaking). For instance, they would put on hold expensive plans to renew our Trident nuclear deterrent, they propose a one-off amnesty on illegal immigrants, and they strongly favour joining the single European currency, though only when the time is right, and not before consulting the British people.
Can't think of anything else off the top of my head.
EDIT:
Oh yes, Iraq. Lib Dems were strongly opposed to it, while Tory and Labour were for strongly for it.
Also electoral reform. Tories want to stick to FPTP that favour big parties. Labour were the same for ages, but are having something of a deathbed conversion. Lib Dem have always favoured PR.
Some more here:
http://news.bbc.co.uk/1/hi/uk_politi...es/default.stm