Hello,
The bit you need to edit is in the [url=http://heartoflove.net/skins/natural_pink/rsc/styles.css]styles.css[/url] file for your skin:

.bText {
	margin-top: 0px;
	margin-bottom: 0px;
        font-size: 80%;
}

The "font-size" line is not there now, just add it in like this and the post text will get smaller.

If you want to learn some css, [url=http://www.w3schools.com/css/default.asp]this is a good place to start[/url].

Thank you so much mwah! mwah!
I did like you said and yes, now they are smaller. I'll take a look at the css tutorial website. I am not really smart with codes, but I'll try my best.

Thanks a bunch. ;)