I too have very weird dreams from time to time, and I was on Lexapro for over a year. I didn't notice any increase in intensity or weirdness. The one thing that has giving me the most intense and frightening dreams is nicotine patches. Though, I'm on wellbutrin now, and have been for about a month. Two nights this past week, I woke myself up my performing the action in my dream physically with my body.

The first was I woke up kicking and jumped out of bed. I was dreaming that I was kicking a guy's winshield in. The second was someone offered me a cigarette. I kept trying to put it in my mouth, but I couldn't do it. I'd get my hand right up to my mouth, but something was blocking me. I wear a special mask at night for sleep apnea and my hand kept hitting the mask until I woke up!

Having said all that, it's certainly possible that lexapro is having an effect on your dreams. I just didn't notice anything when I was on it.