Is there a way to copy text that is colored, bold, underlined, etc to lets say Notepad without the special characters that make them colored, bold, underlined, etc?

No.

Well actually, I think I misunderstood your question...

If you want to copy text without colors, bold, underline
and reverse, just highlighting the text without holding any
keys will automatically copy the text to the clipboard. If you
want to retain the colors, underline, bold and reverse, in the
copied text, hold only the CTRL key while highlighting.

Those special characters are called control codes. Control
codes for color, bold, underline and reverse color text.

been using mirc for years and never knew that

Notepad as a text editor doesn't support richtext, while wordpad does.
However if you want to copy mIRC text containing control codes, press CTRL key while copying, but still this won't allow you to paste the line in a richtext editor and they are colored, as mIRC behaviour with control code is different from windows text editors.