HTML4.01 is OK. In fact, the overwhelming majority of websites are still on HTML4.x.
Your site is small. As such, you should ideally develop and test it in Eclipse. The 2 possibilities are: a full installation of the trial version of CFBuilder (based on Eclipse) or an installation of Eclipse together with CFEclipse plugin. Of particular interest to you, both have an elaborate search facility to enable you to locate a file or even a line of code.
If you encounter any difficulties, feel free to ask. Have fun!