Is it better to get charges in Europe in euro or Canadian dollars

Not sure what that 2.5 conversion rate means. Most credit cards convert based on the prevailing exchange rate that day. Having said that if you choose Canadian dollars you are opting into Dynamic Currency Conversion, which usually gives you an unfavorable conversion rate and possibly hidden fees. Always charge in the currency of the country you are visiting, in this case Euros.

Get a credit card with zero foreign transaction/conversion fees (e.g. Capital One). There is no reason to pay a 2.5 conversion rate, since many credit cards have none. You don't want to be charged in anything BUT the local currency, which is Euros. If you ask to be charged in Canadian dollars, who knows what exchange the hotel will use (it will definitely have a markup).

No. If you ask your hotel to charge you in CAD, you are inviting them to invent whatever exchange rate they or their bank like.
Credit card companies (Visa, Mastecard), convert at the Interbank rate, which is the best you can get.
Your bank may add a "Foreign Transaction Fee", but that is another matter, and hey will charge that whoever does the conversion.

The same applies to getting cash out of cash machines (ATM). If it offers you a choice, always go for the currency you are actually getting out of the machine.

I think you have mistyped, according to Google, the current rate is: €1 = 1.50 Canadian Dollar

OK, I think you are talking about two different things. A transaction fee is one thing and as the previous poster said get another credit card that does not charge this. Conversion rates-charge in Euro's only let the credit card bank do the conversion into Canadian dollars.

It's complicated for you. When we travel overseas, we charge on a card with no transaction fee. We always use the "local currency" for charges because the bank's exchange rate is better than what the hotels, etc. would use (Last year, there were a couple of places that asked us if we wanted to charge in dollars or euros). If you charged in Canadian dollars, would there be no conversion/transaction fee? Is there any way you could find out the exchange rate of your hotel vs. the bank? Have you checked all your cards to see if you have one with lower or no transaction fee? I know in the US, AAA's card has no transaction fee

When I am offered at check-out by the hotel to be charged in US $ or Euro, and the exchange rate is presented to me, I opt for the amount to be in Euro, ie run the credit card through in Euro. I am not interested in the dollar amount given by the DCC since I am paying by Visa credit card. The dollar amount along with original Euro amount will appear on the credit statement. Then I figure what conversion was used in determining the $ amount.

from wikipedia - Dynamic currency conversion

When I use my Capital One card, I get full credit according to the exchange rate as of that time. They don't discount at all.
My Wells Fargo ATM card charges $5.00 and 5%--pretty poor deal--for cash advances. I use a credit union ATM for the little amount of cash I withdraw for walking around money. I charge everything possible.
You need to get another credit card for traveling. I use the Venture card that pays me 3% of everything charged when used for travel related charges.

And if you have the chance to charge things in different currencies, choose to take the charge in Euros.

My Visa card charges me 2.5 conversion rate. Should I ask hotel etc to
charge me in Canadian dollars? Would this be cheaper?

NO!

Your CDN Visa will convert your Euros spent at a rate 2.5% above that day's benchmark rate.

If you go down the Dynamic Currency Conversion rabbit hole ( allowing a hotel, retail store or ATM to convert your purchase to CDN $$), then you are allowing them to charge whatever exchange rate they want. And that will NOT be in your best interest.

Unfortunately, in Canada, you aren't going to find a better deal than the one you've got now.

Interestingly, Canadian Capital One credit cards charge a 2.5% foreign conversion fee. in fact very few Canadian cards waive the fee. Here is a recent article that links to the 4 cards in Canada that don't charge foreign conversion fees. Looks like we Canadians are being charged for travelling so much...

EDITED to add: Chase is no longer offering the Amazon.ca card so the possibilities are now even fewer...