I use a Native Instruments S4 wi Traktor pro and Native Instruments Maschine for sequencing and sampling on the fly etc. I've used both Serrato and Traktor and in my opinion and every DJ/producer i know (apart from the few who are scratch dj's) much prefer the workflow and layout of Traktor. Get yourself onto The Native Instruments Traktor Forum as that'll help you with any queries or problems you may have, also check out all the Traktor instructional vids on the NI website as these will open up areas of traktor that you may not be aware of - if you can afford it then NI were doing cheap upgrades to the full version of Traktor - something you may want to explore further if the LE version is feature locked.
Spend some time optimising your laptop to run Traktor, switch off everything that may have an affect on memory usage and dial in your latency as low as possible, make sure your tunes are categorised correctly in itunes, it took me a couple of years in total doing quite a few tunes a day to label correctly 8000+ tunes and add ID3 tags with such info as BPM/Key/Genre/artist/remix artist//label/sub label/artwork etc and imported into Traktor's library and i dunno if you play/mix by "Key" when your DJ'ing but if you do then Yakov's - mixed in key software may be of benefit to yourself as learning what key changes work best with tracks is an easy way to add some genuine polish to your mixes.
Don't think you have to avoid the sync function to be a proper DJ, I know quite a lot of Pro DJ's through booking them for festivals and club nights (darren emmerson/meat katie/elite force/krafty kutz/utah saints/loops of fury/andrew weatherall etc..) and they all laugh at this argument that you have to beatmatch by ear all the time, it's kinda like the rigid/fixed/ss is the only way to ride off road argument put about by luddites and snobs, anyone can learn to beatmatch - it's not hard in the slightest so why hold yourself back? - learn how to fully utilise all the tricks and treats that Traktor has and you'll be a far better DJ than one who stands there in his horsehair shirt fretting and frowning whilst getting that beatmatch perfect, the crowd will have wandered off to another room by this time.
I've been messing about wi "Dj controllers" for 5-6 years now and it was the best thing that could'a happened, as i can remix on the fly and if i route/use the Maschine controller as well it's an absolute hoot and fun to use, there's still a place for my 1210's and hefty record box but i could turn up anywhere that has digital decks running traktor and plug in my USB stick with my traktor logs/tunes and play just as well (or badly depending on your point of view) as i can at home on my personal set up.
Check out ellaskins/dj tutor on you tube, he's got a lot of tips n, tricks for someone new to dj controllers.
Most importantly have fun...there is no right/wrong way to dj, whatever works for yourself is the correct way and if folk are dancing and having fun then that's all that matters, tell the music snobs to buggeroff.