In my LaTeX document I've got a table of contents that is automatically generated by collecting everything that is of the form \chapter.
However, I've got an acknowledgements chapter before the table of contents and I don't want it to be automatically labelled "Chapter 1" or captured in the table of contents. Should I be avoiding \chapter altogether and use \section instead? I want to keep the font/formatting that other chapters have though.
The usual way to handle that kind of thing is with the \frontmatter command. Put it after the \begin{document}, and then put \mainmatter right before the \chapter you want to correspond to chapter 1. This may only work in the book class. If you're using \chapter in a report, then \chapter* should also create a chapter that has no number and won't show up in the table of contents.
Indeed, as unknown (google) mentioned, using \frontmatter and \mainmatter is the best solution. This will also adjust your page numbering to lowercase roman numerals for the front matter. However, it works only on book and similar document classes.
In case you're using report, try \chapter*. This will create a chapter without a number that does not appear in the table of contents.