HTML question

[tigertoy]

What is the simplest/best way to control the line spacing of HTML lists?  I'm specifically talking about putting a list in an LJ entry, so I don't have a separate style sheet I can reuse and I want something concise.  Specifically, I want to avoid having any extra blank lines before and after the list and between the items.

I want HTML that looks like this:

Regular text
<ol>
<li>Item</li>
<li>Item
Second line of item</li>
<li>Item</li>
</ol>
Regular text

That renders like this when LJ displays it (line spacing only, I'm not showing the indenting):
Regular text
1. Item
2. Item
Second line of item
3. Item
Regular text

As opposed to
Regular text


1. Item

2. Item
Second line of item

3. Item



Regular text

For reference, the sample above with the <'s not escaped actually renders like this.  It does look like the immediately above text in my journal on my browser.

Regular text

1. Item


2. Item
   Second line of item


3. Item

Regular text


Also: do best practices include a </li> at the end of each item?  I thought all tags were supposed to have ends, but the examples on the W3C web site don't use </li>. Hah, I answered a part of my own question: if I leave out the </li> it doesn't put a space between the items, but it still puts extra lines at the beginning and end. But I want to know if leaving out the </li>s is going to screw up somebody else's browser. Or if putting them in does.

Yes, I did spend some time trying to look this up myself, but I don't want to spend all day learning HTML.  So please don't point me at a reference web site unless you can point me to a specific page on that web site that answers my question.