Suica vs. tourist pass

Hi I will be visiting Tokyo for about 17 days (4 days will be in Hakone/Fuji5) and my question is should I buy a Suica or opt for the unlimited rides tourist pass?

If the only long-distance (inter-city) travel you are doing is between Tokyo and Hakone & Fuji 5 Lakes area, then you don't need any of the nationwide Japan Rail Pass, if that is what you mean. Japan Rail Pass (JR Pass) is good for traveling long-distance on JR Shinkansen limited express trains, like Tokyo - Kyoto/Osaka, or further onto Hiroshima and back to Tokyo, etc.

Also note that JR Pass is (as the name suggests) good only for "Japan Rail" company's trains. Inside and around Tokyo, you will be riding JR local trains, subways, etc., that prepaid cards (either Suica or Pasmo) would be fine.

For going to Hakone & Fuji Five Lakes area, you might consider an area-specific pass.

Hi I am referring to those 24/48/72-hour tourist pass here. http://www.tokyometro.jp/en/ticket/value/travel/

If you are not familiar with the Tokyo and finding your way around the city, then the passes may be useful for you to jump on and off the Metro without worrying about having to pay for every ride. However if you do your homework and familiarise yourself with the system and how to get around, then you are not likely to find much savings with the passes as many of Tokyo's tourist destinations are along the Yamanote line which is a JR line and not covered by the passes.

Without basic information about your trips,
it is hard to make a precise answer to your question.

Which sites do you plan to visit?
Where in Tokyo will you stay?
How is your timeline?

It depends on the day.

If, for instance, you plan to go to Disneysea, and spend the whole day there, you will just be paying for transportation to and from there. Uning a Suica for these two fares is probably less.

If, on the other hand, you are planning to go six different places on one day, (Tokyo Tower, The Imperial Palace Gardens, Akihabara, Ueno, Asakusa, and then Tokyo Skytree), then a day pass might be a lot less than the seven fares that you need between these locations.

If, for a third example, you are in Shinjuku, and decide that you are going to spend the entire day just walking around Shinjuku, you do not need either.

None of these are unreasonable plans for a day, and each has a different outcome.