Anakin fell to the dark side because he, like all villains, was weak. If a villain wasn't weak he'd be a hero like Luke. His reasons were lame because they were bull, lies he was telling himself to justify his betrayal of the Jedi. At least that is my take on his fall. This is the order I like the Star Wars films in from best to worst:
1. TESB
2. ROTS
3. ANH
4. ROTJ
5. AOTC
6. TPM