I think I'd go for ケーレン for your name. The long dash extends the 'e' sound, which imitates the greater stress that the first syllable has in English and makes it sound roughly like 'care'.
I learned the kana in sequence using the JapanesePod101 Kantan Kana video series. Once I could write them, I found that the characters that had previously looked very similar actually started to look quite different. And it became a lot easier to read advertisements, movie posters and magazine covers because even if they use a stylised, funky font, they pretty much follow the rules about the way the characters are written.
If you're using Windows 7 there are some nice clear instructions on how to set up Japanese keyboard input on this webpage: http://www.coscom.co.jp/learnjapanese801/msime_win7_en1.html. It also explains how to type in Japanese, which you'll find is actually surprisingly straightforward. For example, if you want to type 'nihongo' in Japanese, you type 'nihongo' and as you type the letters will be converted to hiragana, so you get にほんご. If you hit the space bar at this point, the hiragana will be converted to kanji, giving you 日本語.
マイケル