Review:
There are probably very few people on Earth who use computers, and have never heard of or used Notepad before. Notepad is the (in)famous text editor of Windows. The roots of the program can be traced to Windows 1.01 which was released way back in 1985 although Notepad has not changed much since its first release. In fact, it was not until 2000, Microsoft cared to update Notepad notably. The Windows 2000 version of the program finally supports virtually unlimited file sizes as compared to the previous 64K limit, and it now has a search/replace feature.
Notepad is an extremely powerful program and is very often under-estimated. Notepad can easily handle most of your needs for writing things down. It uses very little RAM, so you can save ram for your bigger applications.
The only suggestion I would have to say is to include line numbering, and I am actually quite surprised it isn't available yet.