Robin Williams is great and all, but he's no Teddy Roosevelt. I reserve that honor for John Alexander, the man who played Theodore in Frank Capra's wonderful Arsenic and Old Lace. (As well as Bob Hope's Fancy Pants!) Ever since I was a little girl, his work as the Roosevelt-obsessed brother of Cary Grant has always sent me into fits of laughter. Teddy's earnestness has a charm we don't often see, and that bugle -- I almost wanted one of my own to Charge! ahead.
If you've never seen this Capra film, you must. Some rave about that Christmas flick, but for me -- it's all about the perfectly paced black comedy. In fact, this is the film that hooked me into the world of dark comedy, and I never looked back.
Trivia (via IMDb and Wikipedia):
Capra was forced to cast Cary Grant in the starring role. He had been looking through the likes of Jack Benny and Ronald Reagan, and almost got to give the role to Bob Hope, but there was a contract issue with Paramount.
Raymond Massey, who played the creepy brother Jonathan, not only looked like Boris Karloff -- he also took over the role. Karloff was playing it on Broadway while the film was in production, so he couldn't join the cast.