There are a handful of differences between a simple mortgage renewal versus refinancing.
At a very high level, when you do a simple renewal, it's just that. No new application, no credit check, and you don't get access to any new or additional equity such as a HELOC. As opposed to refinancing, you'll require a full application process again, it may open up opportunities to equity, such as a higher HELOC if you need it, there may be additional fees (ask to be sure), and you'll be subject to new terms and conditions. This is where your guy at TD wants to push you so he can get a commission on the refinancing process and HELOC.
If you don't need a HELOC, or you don't want to access the equity of your house (Say $250K) to spend on female companions and illicit drugs, or to buy cars you don't need w/o your wife knowing, then perhaps a simple renewal will do the trick. But if your goals involve some requirement to access equity for whatever reasons it may be (we're not here to judge!) then perhaps consider refinancing.
Ask around. Shop around. But whatever you must do. Trust the folks on Revscene (except for me, of course.)