I've become a huge TV geek over the last few years, which could help explain my lack of interest in all things current wrestling wise (still watch old episodes of RAW and Nitro + old PPVs on WWE 24/7). These are some of the reasons why I'm stuck inside glued to a TV many nights.
The X-Files - Still probably my favorite television show of all time. The only other show that could compare to it in my book is the next show I'll talk about. What do you really need to say about the X-Files? It was a cultural phenomenon and a sci-fi/horror geek's wet dream. David Duchovny's portrayal of Fox Mulder is one of the greatest characters in all of science-fiction in my opinion. Not much else you can say about the X-Files except that it was one of the most intelligent, well-written, and above all engrossing television series ever created. Chris Carter doesn't ever have to create another piece of work and will still be regarded as a Sci-Fi legend.
Lost - I've only been watching this show for around a year or so now, but my god this show has quickly rocketed to the very top of my all time favorite shows list. Everything in this show is amazing, the acting, the writing, the directing, the atmosphere, the music, everything. This, more then any other show, has left me with my jaw wide open at the conclusion of many an episode. Never before have I seen a show that is so incredibly engrossing; you watch one episode fully to the end, and the ending of each episode will leave you usually wide-eyed, jaw open, saying "WHAT THE FUCK?!" and demanding that the next episode be played. You just have to know. Absolute genius show, and never before have I seen a show that so easily mixed every genre known to man. Drama, horror, sci-fi, suspense, comedy, romance, action, you name the genre and odds are that Lost has incorporated many of it's elements into the show. This show will live on forever as one of the most beloved and for having one of the most loyal and rabid fanbases ever.
The Twilight Zone - No show terrified me, or shocked me, as a child more then the original Twilight Zone created by another all time legend of sci-fi/horror, Rod Serling. There are so many classic episodes of this show it's just downright ridiculious, as if the huge influence this show has had on all of pop culture since. Most people probably have seen countless parodies or rip-offs of Twilight Zone episodes in their lives, hell a good 1/3rd of all the Simpson's Treehouse of Horror parodies are based off of TZ episodes. No show has ever utilized the twist ending better then the Twilight Zone.
Tales From the Crypt - Another show that had me jumping 10 feet across the room to my bed at nights in fear of what was under it as a kid. I remember staying up late with my father watching classic episodes of this show, and always finding a mixture of horror and comedy in a perfect blend. Every horror geek could tell you the massive impact that the original EC comics had on the world of horror as we know it. You'll be hard pressed to find a better show to watch when you and your buddies just want to hang out, get drunk, and have fun.
Star Trek (Original, The Next Generation, Deep Space Nine, & Voyager. Fuck Enterprise.) - What can one truly say about the massive and astounding world canon created by all of these great series? I won't go very much into detail here because then I'll end up writing 10 pages alone on the original series. Needless to say, I've become a hardcore Trekkie this year, fully plunging myself into unabashed nerd-dom. I'm only a comic-book collection away from never getting laid again. All I have to say is that if you even mildly enjoy science-fiction, you had better sit your ass down and give Star Trek a chance. I'm insanely glad that I did. (And I also must comment on how underrated Voyager was. Gets lumped too often into the "bad Star Trek" pile and very undeservedly so.)
Freaks & Geeks - By far the greatest show to ever chronicle high-school life. You want realism? Fuck 90210, you better sit down and catch the mind-numbingly brilliant show that was Freaks & Geeks. Never before has a TV show made me feel nostalgic for a period of time that I didn't even grow up in (the show was set in 1980). Hilarious and heart-breaking, this is the show that jump started the careers of ALL of the big current comedy players. This is where Judd Apatow, Seth Rogen, and James Franco all got their breakouts. Seriously, do yourself a favor even if you've never seen the show and just go but the Complete Series DVD (it's something like 40 or 50 bucks). You will NOT be disappointed.
Honorable Mentions: Fringe, Family Guy, South Park, 3rd Rock From the Sun, Spin City, 24, C.S.I., The Office, The Simpsons, My So Called Life(and yes, I do feel gay for mentioning it but it was a genius show), the Wonder Years, That 70s Show, Millenium, Dexter, Tales From the Darkside, Friday the 13th: The Series.
Probably forgot a bunch.