Comment Don't (Score 1) 112
Want to rewrite to be more "modern", ask netscape. Wait, you can't. They pulled the same stunt and lost valuable time and went out of business. If you still update these sites, try refactoring just the bits you need to update. If you update them often enough, you'll have an updated application and you'll learn refactoring skills in the meantime.
You would only undertake the effort if it gave a payoff in return. Will your visitors "see" a difference? Will they care they are browsing on a "modern stack"? Probably not.