There are loads of interesting things to cook ...far too many to suggest in one post. Have a look at some websites .BBC is good.
Depends what you like to eat ..as it's supposed (lol) to be summer what about a nice Greek salad and some new potatoes boiled in their skins with a steak.
Tonight we are having stuffed belly pork braised with celery ,peppers,carrots and bacon with mashed potatoes.
If you go to work and have to cook when you come home it is hard to gather any enthusiam ..I know ..been there got the T shirt.. have a look here...
http://thefoody.com/home.html
Also if you like stews ,casseroles etc ..invest in a slow cooker ....brilliant if you are out all day.