Not sure about what you mean by “cheerful”, but these are all quite light-hearted/funny.
Watched them all, and should all be OK to watch. I will put an X in front of those that I would definitely recommend.
X Lucky Star
X Chi’s Sweet Home,
X Bakemonogatari,
Baka to Test to Shoukanjuu,
Bokusatsu Tenshi Dokuro-chan,
Powerpuff Girls Z,
X Midori no Hibi,
FLCL,
Genshiken,
Girls Bravo,
X Great Teacher Onizuka,
Shinryaku Ika Musume,
Hayate no Gotoku,
X Jungle Wa Itsumo Hale Nochi Guu,
X Kyouran Kazoku Nikki,
Makai Senki Disgaea,
Nichijou,
X Ore no Imouto ga Konnani Kawaii Wake ga Nai,
X Panty and Stocking with Garterbelt,
Ranma ½,
X Renkin San-kyuu Magical Pokaan,
Rizelmine,
Hanamaru Youchien,
X Toradora,
Watamote,
X Sayonara Zetsubou Sense
Oh, and you should (in theory, have not tested it) be able to watch all of them here:
http://www.anime-sub.com/
if not, there are always torrents :P