A Celeron is at the lower end of the CPU scale, it is a cheaper CPU for the low-end market. Not BAD as such, just that there are more powerful CPUs around, but it will do the job.
One word you had in your list above stands out, GAMES.
For most things (e-mail, shopping, word processing, music) about any laptop would do, but playing games is another thing altogether.
Most laptops (and PCs come to that) supply basic or minimum graphics, but games require extra graphics performance and therefore you need to buy a laptop that has a good graphics card.
If you have a low end CPU (like a Celeron) and a low end graphics card, you are just NOT going to be able to play any games.
In fact generally laptops are not the best for playing games, a PC (with the right hardware) is much better.
IF you want to play games then speak to a person who plays games and knows the sort of hardware they require (I do not play games myself).