If you want to tank and are willing to stick with it and listen to advice (or even better, have some friends to help you learn), I would say by all means get the tank gear. Just keep in mind that some players assume that everyone innately knows how to play the game and will get rather upset when you don't. I would suggest that if you queue as a tank, let people know that you are new at it and let them give you advice on how to handle the fights.
On the other hand, you could get the dps gear, go run things as dps, and then grab tank gear as a second set along the way. It will be slower, but if you're not used to many of the fights, don't have friends to help, it might be a better alternative depending on your temperament.
In either case, do a bit of reading up on the fights and how to tank/dps (specs, rotations, gearing priorities, etc). Since you're a guardian/jugg (given the strength comment), I will point out in particular that you have a skill that I do not know the name of that looks nice for tanking on first glance (it increases defenses or something), but it also drops threat hard, so don't use it in general (it may have situational uses... my tank is a shadow, so I don't know very well).
If you're on Prophecy of the Five on Republic, look me up if you have questions. Main characters are Inua (commando dps/heals), Unia (shadow tank), Naui (gunslinger), and Ainu (guardian, still leveling).