Since my time in London and Paris is so short, would it be a good idea to book city guided tours instead of trying to see everything myself? How is the best way to find a bus tour that is worth while and economical? Any suggestions??
A bus tour is only as good as the route it travels. You won't learn anything special or unique on a bus tour. Both of these cities offer a myriad array of affordable and interesting walking tours and bike tours, with guides you can ask questions from, and who have invested large amounts of time researching their subject. Check Rick Steves & Trip Advisor for tour companies. Read their reviews and see if they offer the themes that interest you the most.
A high point of our trip to London was interest-driven walks by London Walks. I would look at companies that offer general and specific interest walks in the two cities. The walks should be reasonably priced.
Regardless of city or county this is a frequently asked question, guide vs own, that really is not an either or type of question. Personally believe that a guide always provides a better experience than simply doing the same thing on your own. Obviously a poor guide could be a problem but we have never had a bad guide. A couple were so so but in general they have all ranged between excellent and outstanding. A guide will vastly increase your efficiency in getting from one site to another, may skip entry lines, provide additional insight and may point out small sites that may not make that printed walking guide. If short on time, then a guide is the way to go. The majority of our tours over the years have been arranged through the local TIs. That is where we always start unless we have a recommendation via a guidebook or web site.
I suggest you try the HOHO tours, the taped commentary is basic, but the buses go by all the major tourist sites, and you can hop on and off as you wish, so spend time where you wish. The regular big bus tours are drive by tours, you do have a guide, but she/he usually has to give the tour in several languages, so there isn't much interaction( in other words you can't ask specific questions easily, so its not much different then a taped commentary). Driving by sights isn't really much of a visit either. In PAris I have used the L;Open Tour Buses. They are bright yellow and green, you pay for tour when you board bus( no prebooking needed) and you can get a two day ticket for only a few euros more then a one day ticket.They have four routes , and as I said, they will take you to all major sights. I find you really need the two day pass to do all the routes if you plan on getting off and visiting anything. You can google for their websites , L'Open Tour Buses. The two main big bus tour companies are ParisVisions and Cityrama( which I beleive have recently merged ). They also have an easy english website to look up. A walking tour would be a great way to get a more indepth look at sections of paris and although I haven't taken one I would recommend them. Pariswalks is well reviewed, as are several other companies.
How much time do you have in each location?
About three days in each city....
My suggestion would be to use the HOHO buses. They are good introductions to the city, and you can get off and explore at any time. The tickets are good for the whole calendar day (or 24 hours - different in different places), so you can use them just as transport, too. See how far you get, then do the rest on your own.
Suggestion - Read the reviews for HoHo buses on Trip Advisor or for any other bus tour in which ever city you are going to and then read the reviews for any other tour. Which ones sound like they are interesting and good value for money?
The problem with tour reveiws is I personally have used the hohos twice, yet I have never posted a review on them. They are what they are, and the complaints tend to be because people expect them to be more then they are.. the tours are taped, the commentary is basic, and yes, sometimes I had to wait 20 minutes for next bus.. but for what I paid, and the ease of use I was content with them. If a person has more then 2 days , and enough time to do some research, I would say do it on your own using the metro, would be faster and cheaper, but thats because you would have to invest your time doing homework, and making a plan and routing your way around. I enjoy that ( both times I took hoho is because my kids love them!)
I have used Hop On Hop Off buses in both Hong Kong and Cape Town. I highly recommend them as excellent ways to get around the city at your leisure. The complimentary headsets provide at great deal of information through the commentaries. And the price can't be beat.
If you like doing a lot of advanced planning yourself then get a guide book (our host has a good set for this kind of thing) and even download some audio tours. You can then be your own tour guide and do things on your schedule and terms. I did this for my wife and we had a wonderful time. If you don't have the time or inclination, a tour guide might be better for you and a good one would be a worth while investment. I would do it early during your visit because I think the over view and information will make the rest of your stay more interesting and informed.
When considering a city tour, read the itinerary carefully. If it says "see xxx" that usually means you will drive past it and see it briefly from the bus. If it says "visit xxx" then you will enter the sight. In Paris, I'd recommend starting with a Fat Tire bike tour instead of a HOHO bus. That will give you an overview of the city with some interesting facts and anecdotes mixed in. There will be stops for photos.
Oh yes, if its not raining I totally second Chani's recomendation to do a Fat Tire Bike Tour, they are fun, and easy( central Paris is mostly pretty flat!)