My priest told me that first of all during Great Lent, we should abstain from sin.
I had a hard enough time this year keeping the fast from food. It made me quite depressed at times. If I'd had to fast from entertainment as well, I don't know how I would have gone.
Some entertainment is good, though. This story might be inspiring:
This hunter was going across the hills and he saw St. Antony with a group of monks. The Saint was telling jokes and anecdotes, and the monks laughed, which scandalized the hunter. Antony saw that, approached the hunter, and said: "Please, brother - pull the string of your bow."
The hunter did, and the Saint said: "Pull it harder!"
He did. "Harder!"
"I can't Father - the string will snap!"
And St. Antony said: "Well, that is what will happen to their souls as well if we burden them too much."