In the special additions many new special effects shots were added like a MUCH more developed and illustrated cloud city and the bit when the Millennium Falcon takes off from Tattoine escaping the storm troopers in the first film you actually see the MF take off and blast into orbit which was an entirely new shot! Those aspects never bothered me, in fact I think the films look all the better for it the problem with the special editions lies in one scene in particular.
In the cantina at Mos Eisley, when Han is sitting across the table from the bounty hunter Greedo. In the original film Han shoots Greedo under the table because he is about to be captured, its almost done in cold-blood which makes Han's character more interesting. However in the Special Edition Lucas felt he should make Han's character more kiddy-friendly and had his computer geeks alter the scene so Greedo shoots first meaning Han had more reason to kill him which really alters Han's character IMO.
Also in the special editions Han talks to a CGI Jabba outside the Millennium Falcon in the first film, that was a scene that was originally cut as they had no way of making a realistic Jabba (possibly due to budget) so they added a CGI Jabba and had Han digitally 'step' over Jabba's tail which is a horrible, horrible piece of cut out and paste CGI. I'd like the Special Editions much more if it was just special effects scenes that were added and not actually change to the story.
Lucas created something very special with the original trilogy 25 years ago but the success was also down to the fantastic cast, the freshness of it all, a legendary score and some ground-breaking special effects as well as Lucas. He simply doesn't have those elements this time round and has his head up his ass with regards to CGI.