for me personally, The X Files was, and still is, the finest series ever. it encapsulated much of what people (particularly Americans) were feeling about governments, cover-ups and the paranormal in the early 1990's when it was first broadcast. its engaging without resorting to pyrotechnics and action sequences. you could see its influence in the 1990's with all the merchendise, rip-offs and the fact the postman could whistle the theme tune!
the first three series' are almost flawless. the first, introducing us to the characters and certain themes which carry on through the entire series, while the second series lays out a much more expansive and ambitious front in the form of the Mythology story arc which will continue through to the very end (Scully's abduction, the Colonisation story arc). overall, it was the creative story telling that really engaged viewers. highlights from the first few series include the chilling Tooms, Beyond The Sea featuring (arguably) Gillian Anderson's finest performance to Darin Morgan's hilariously off-beat Humbug and the epic multiparter Anasazi, Blessing Way and Paper Clip.
another of TXF's strengths was creating some brilliant characters - Mulder, the believer on a personal mission to uncover the truth; Scully, the sceptic; and their by-the-book boss, Skinner; everyone's favourite double-crossing Ratboy Krycek and Cigerette Smoking Man - one of the best villains in TV history.
some later series' suffer in quality (series 7 in my opinion is really bad) and some of the 'monster of the week' episodes begin to tire as the writers ran short on ideas (there are only so many stories you can write about ghosts and monsters...) but i always felt the Mythology episodes carried TXF through.
some fans have slagged off series' 8 and 9 because the John Doggett character. i have to disagree with the criticisms. he's a great character and adds a new dimension to the series while other old reoccuring characters (Skinner, Krycek) step into centre stage, series 8 is a real favourite of mine.
while the Mythology story arc was great, it was also a weakness - for the casual viewer, it was tough following such an elaborate story. TXF didnt always provide the usual plot cues as most TV dramas usually would. the viewer had to work out what was going on themselves as the writers refused to patronise the viewers, and this alienated some viewers and fans (what the hell was a viewer suppose to do if they missed *that* crucial episode?!). this DVD boxset should redress this injustice by compiling everything series 1-9 and the 1998 'Fight The Future' blockbuster film altogether. its engaging and tough, but one of the most intelligent and rewarding series' ive ever known.