I'd say two hours is more than you'll need to get into Venice, especially if you haven't checked bags. Here's a very comprehensive description of transportation options. Either bus (ACTV or ATVO) will get you to Piazzale Roma in less than half an hour, and runs frequently during the day and evening. Unless you arrive very late at night or early in the morning, or it takes a long time to deplane and/or retrieve bags, you could expect to get there within an hour. This is probably faster than any water transport from the airport.
From Piazzale Roma you can reach your hotel by walking, vaporetto, or a combination. How long this takes depends on where your hotel is. Not knowing when you'll be there, I can't tell how realistic your price points are, but I'd guess you'll pay closer to the high end than the low end for anything in Venice itself for three people. Look for a hotel in Cannareggio or Santa Croce for a shorter trip on arrival, maybe Dorsoduro if you don't mind some time getting there. Generally, the closer you are to Piazza San Marco the more your hotel will cost (other things being equal). Booking.com is a good search tool, but try to make the actual booking on the hotel's own website.
EDIT -- Replying to your last question, yes you'll find plenty of dining options after 9:00. Also, since you're flying from Paris you won't have to deal with immigration, and customs will be a matter of going through a door signed "nothing to declare."