I personally feel that title music in video games are highly underated. A memorable title theme can go a long way. Rather it be a looping piece of music or a short 15 second piece, the value of a good title track is not to be underestimated. These are some of my absolute favorite title themes I've been privlaged to hear since I've been gaming.
Title - Mega Man 3 (NES)
The title music to Mega Man 2 was accompanied by an intro tune, which is a redone version of part of the ending theme of the original Mega Man game. As awesome as Mega Man 2's title music is, Mega Man 3's is far and away the superior track. When you turn on Mega Man 3, there's no intro scene to go with the title music. If you're patient and let the music build up to the main course, you're treated to one of the finest pieces of video game music ever composed. With the very first track you hear, composer Bun Bun already cemented his status as a fan favorite Mega Man music maker. Not only does Mega Man 3's title theme get you pumped to play the game, it's an amazing tune on it's own.
Wings For My Way (GX Advertise) - F-Zero GX (GCN)
Talk about rocking out. When I first turned on F-Zero GX, I had no idea the title music would grab me by the face in the same way the rest of the game did. Over 3 minutes had passed before I hit the start button. GX's title music is lengthy, sure, but it stops at around the three minute mark and already my jaw had hit the floor. I was just as impressed with the music as a I was the visuals but the title music is what really sold it to me. Called "Wings For My Way (AX Advertise)," F-Zero GX's title music is even more hardcore than that of F-Zero X on the N64 and sets the tone of the entire game and the game's soundtrack. Repeatidly listening can actually melt your face clean off. It's that awesome.
Title - SimCity (SNES)
I've played a PC version of SimCity before but the SNES version is special to me. Mind you, I suck at the game and get removed from my mayor duties pretty quickly, but it's still fine. Interestingly, I didn't play the SNES version of Will Wright's city builder until the year 2000. The game's endearing title music plays over a city backdrop at night. It's a short looping tune, but it's so relaxing. Makes me wanna lie down and star up at the stars. If SimCity's SNES title theme doesn't move you at all, you're probably dead inside.
Title - Mega Man X (SNES)
For those of us that don't live in Japan, (which is quiet a lot), Mega Man X's title theme was probably the first time a rock element had been added to the soundtrack. Mega Man X's music is heavily rock based and what better way to demonstrate that than with the the game's first song. It's short but it's very, very sweet. Of all the title themes for the X series, this one is undoubtedly my favorite.
Theme of M.U.S.H.A. Aleste - M.U.S.H.A. (GEN)
Being one of the games in Compile's popular Aleste series, MUSHA's title them isn't new but the rendition done with the Genesis sound processor really make this version stand out. It's a little dark in tone so it's definitely not an upbeat theme, but it still sounds epic.
Title Screen - Contra (NES ver.)
Clocking in at only 8 seconds long with an explosive sound effect to add to it's awesomness, Contra's NES title music rendition is one of the most memorable jingles on this planet. It screams "Let's do this!" Play this track and watch a room full of gamers swoon with nostalgia.
Title Theme - Double Dragon (NES ver.)
I'm going to come right out and say it: the original arcade music for Double Dragon sucked. It sounded like early Genesis music where the sound composer had no clue how to really take advantage of the the unit's sound chip. The NES version is light years ahead of it. Double Dragon's NES title theme is one of the most fondly remembered tunes in video games and lets you know that Billy and Jimmy Lee are going to bust some heads.
Title Theme - Adventure Island II (NES)
A very short jingle, but still one of the greatest. It's upbeat, catching and is entertaing from the first note to the very last.
Title - Pilotwings (SNES)
This is another short title theme and the developers of the Pilotwings series must have known they'd hit gold because it's been used in every Pilotwings game ever since.
The Prelude - Final Fantasy IV (SNES, PS, GBA)
With a few exceptions (FFV, FFVI, FFVIII and so on), Final Fantasy games have been using a title theme known as "The Prelude" since the very first installment on the NES. Of all The Prelude themes, Final Fantasy IV is in my humble opinion, the pinnacle of the bunch. Just something about the way Nobuo Uematsu composed the SNES version in FFIV that make it sound positively beautiful, yes, even moreso than the one in Final Fantasy VI, which is my all-time favorite FF.
Fear of the Heavens - Secret of Man (SNES)
Along with the Squaresoft logo on the screen (long before the company merged Enix), howls can be heard in the background. The title drops and three youths are seen looking at an enormous tree as the stunning "Fear of the Heavens" title theme plays. Oh, yeah, this game is going to rock. Fun fact: Secret of Mana was originally developed for Nintendo's SNES CD add-on but when Nintendo backed out of the deal with Sony, the game was developed for the SNES instead. One can't help but wonder if this would have altered the audio of the game, but as it stands, the entire game's score is incredible. Another fun fact: Secret of Mana is one of the few games that saw a soundtrack release in the United States.
Title Theme - Super Metroid (SNES)
If Super Metroid's title theme were to be summed up in one word it would be "creppy." Those shots of the lone Mertoid hatchling surrounded by dead scientists only adds to the haunting nature of the piece. Super Metroid's title them wouldn't feel out of place in the least bit in a survival horror game.
Theme of Fire Emblem - Fire Emblem: Seisen no Keifu (SNES)
That subtitle translates to Geneaology of Holy War for those that don't speak Japanese. Like the Final Fantasy series, the Fire Emblem games have used the same title theme in it's many sequels. Of the numerous versions of "Theme of Fire Emblem," Geneaology of Holy War gets my pick for the best one, and considering it's been a superb track in each Fire Emblem game, that's saying a lot.