Well first off welcome.
The only limitation to the trial is the 30 days. Adobe does not hold anything back. And if you decide to purchase, even if you buy a disc, you can just enter the serial number into the trial to unlock it instead of having to wait for a disc or another download. The only exception is the suite because the suite serial numbers do not work on individual trials, only the suite installers which are available from the store (after purchase) or on disc.
The limitation of fonts and font-styles/types are intentional, due to the deployment of websites. It is common that only a few fonts which are installed on most computers will be listed. As a secure method of ensuring your proper font gets displayed by the viewer of your website you should include a font-style as well as a font by name . . . example: "font-family: Arial, sans-serif" where Arial is the font-by-name and sans-serif is the font-style in case Arial is not installed on that person's computer--a similar matching font will display instead.
Would It be a better option to create images in Photoshop using my preferred font then insert it as a image to build the page?
For headers and other misc graphics like that yes. For content no, because if you do it for content your site will never show up in Google or other search engines.
SnakEyez02 gave you a good, simple answer about the fonts. There are however, a lot of other choices. They would take some study to learn to use.
As far as the fonts available in Dreamweaver, these fonts are not actually part of Dreamweaver at all, just choices of font names they give you for convienience.
You can add your own font lists to what is ther by default. ( Format > Font > Edit Font List )
You can simply type any font you want to into the CSS that dreamweaver gives you, but they give you the ones that arfe likely to actually work in most cases.
Browsers will go through the list of fonts and use the first one that is availabe. For instance, if you have the rule:
font-family: "Lucida Grande", Arial, Helvetica, sans-serif;
The browser will use Lucida Grande if it's available on the visitors computer. If not it will look for Arial, then Helvetica. If noe of those are availabe, it will use whatever it's default sans-serif font is. So, you could put "Gil Sans" at the begining of that list, but be aware that almost everyone will still see Lucida or Arial, or Helvetica.
There are ways to embed fonts into the website, but, among other problems, it would increase download time and you may lose people for that.
The problems with text in images are 3 fold.
1) Not visible to search engines. Engines can't index text inside images, so this could negatively impact your site's search ranking.
2) Poor web accessibility. Images can't be "read" by screen readers, language translators or other web assisting technologies. This cripples your site for many users who rely on such devices.
3) Poor rendering. Text in images are often pixilated, hard to see clearly and impossible to increase text only in browser with Ctrl++. Browser Zoom makes images bigger but not always better to read.
Wherever possible, you should use real text with only a few images for your company logo and level 3 headings. But it would be too onerous to build and maintain an entire site around images of text.
Web Safe Fonts:
See this related discussion from last week:
Non Web Fonts in HTML pages.