The Vietnamese place is right across the street from the Purple Turtle. Go to the PT, buy a beer, look back towards the street, and immediately in front of you is the Vietnamese restaurant.
Roatan is very different from the Virgin Islands. Night and day. For what we paid for lunch on VG I can get an A/C room near the water for the night in Roatan. For what we used to pay per night in VG I am now paying per week in Roatan. Big difference.
Food and drinks in Roatan are cheap. A beer at Sundowners, my favorite afternoon/early evening bar is about $1.25. A beer at Purple Turtle, my favorite place to go when Sundowners closes for the night, is even cheaper at about $1.10. For $15 in Roatan two people can eat one heck of a good lunch, compared to $35 - $55 for a similar fare at Top of the Baths in VG. A two tank dive in Roatan is $40, including all equipment, it $110 at Dive BVI for the same. Just about the most expensive place to stay in West End is the Beach House at Half Moon Bay, which costs $200/night for the nicest suite. Compare this to St. Maarten or BVI and you'll see the huge difference.
The other major difference is transportation. In Roatan, we take a taxi from the airport to West End ($15 for 2) and then walk everywhere in West End. If you want to go to the beach, you have Half Moon Bay right there, or for about $4 (for 2) you can take a 10 - 15 minute water taxi to West Bay Beach. The water taxis are available from sunrise to sunset. There is no need or benefit to renting a vehicle. I cannot imagine why anyone would want to rent a vehicle on Roatan unless they had friends on the other end of the island they were visiting with frequently.
Always negotiate cab fares in advance. Be sure the terms are clear to all involved parties. Save yourself any hassles this way.
As for places to eat, should you decide to go to West End:
1. Argentinean Grill - Excellent steaks!! Great food in general. Prices are about $8 - $18 per entree, if memory serves. I don't think you could spend $100 on two people here unless you bought a few liters of wine to go with your meal.
2. The Lighthouse - My wife loves this place. Very romantic setting right on the water. Prices are about the same as Argentinean. The lobster was very good, and the coconut bread was incredible. I had quite a bit to drink first, so the bread was also very theraputic!
3. Chillies - Very inexpensive. Lobster tail w/ sides for about $12. Good food, right on the water at the other end of West End than Argentinean. There's nothing fancy about this place, but Roatan isn't about fancy.
4. Pinocchio's - Up the hill a little from Chillies. Very good Italian themed food. Don't order the garlic chicken unless you are prepared for some serious garlic action. The lobster here was also quite good. I didn't make it here in January when we were down there, but last year prices were about $10 - $15 per entree including sides.
5. Vietnamese Place (I don't know its real name) - Cheap and tasty. Not fancy. Most expensive item on the menu is about $20 and feeds two. Average price on the menu is $6 - $10 per entree. Appetizers are inexpensive. The red thai curry is quite good, although not as hot as I like it. I think it was about $13 after adding a few spring rolls to the order.
6. Sundowners - Lunch and snack foods. Prices are very reasonable. This is my favorite beach bar, and the food is quite good for snack food.
7. The Galley - There is nothing fancy about this place at all. What it lacks in formality it more than makes up for in service, cleanliness, and food. Kristen, who runs the place, is a die hard expat who runs a tight shop. Lunch, including two smoothies, a huge fresh salad that rivals anything I can get here, two sandwiches, and a soda came in right around $20. The smoothies were about $8 of that - they are fresh, delicious, and more addictive than crack cocaine.
8. Josie - This isn't a restaurant, but a super nice lady that comes around West End (and every day to Coconut Tree) with fresh food. She makes lunch on demand (friend chicken to die for) for about $3.50. She also makes the best cinnamon roll on earth. After a two tank dive I get hungry... she is always there to fix that. Her cinnamon rolls are 30L (about $1.50, but we always paid $2 or so).... they are so good that I have found myself daydreaming about them after getting back to the states.
9. Pura Vida - It's a hotel, it's a dive op, it's a restaurant... this is only about the restaurant, as I don't have experience with the rest of their op. The food is good - quite plentiful and reasonably priced. The pizzas are a little bit on the greasy side, but for $8 for a pizza that is big enough to feed two hungry divers I'm not complaining! Their idea of a salad is to cut down an entire field of greens and put it all on the same plate - seldom have a seen a larger salad in my life. Be warned - they make "Italian" food, and by "Italian" I mean they throw a quarter pound of Oregano and Basil on everything.
10. Dian's Garden of Eatin' - Everyone else loves it, we didn't. It was expensive (two people - $40, no alcohol) and I felt that the portion size for the red curry was meant for a child not a full grown man. It's a bit of a hike, maybe 10 minutes, from West End and I would not recommend walking back unless you are feeling daring. We did, and there are no street lights for much of the way. Honduran drivers all aspire to run in the NASCAR races, and the road is curving... The restaurant is located above a furniture store and is quite clean, well decorated, and with impeccably polite and courteous wait staff. If you want to pretend you are in BVI, stop here - everything from the atmosphere to the bill will remind you of other parts of the Caribbean.
I wish you a great trip. I hope some of these comments help. If you dive with Coconut Tree, say hi to PJ, Gay, and Tree for us!