Which should I buy? Mac or PC?

Get a PC.

If you want speedy PC laptop then spend at least $1200 on it(still twice cheaper than Macs)

If you want stable operating system then get Windows 7.

Windows 7 allows you to completely control the power options.Sleeps whenever you want it to sleep.You can also manage Tasks, for example your computer will sleep if one program stops doing some specific process, or when a virus scan ends, e.t.c

All new PC laptops come with at least 250GB hard drive.

I HIGHYLYYYYYYYY RECOMMENDDDDD you spend extra bucks and buy a PC with SSD(Solid State Drive) instead of hard drive and make sure that Solid State Drive is either Intel 320 or Intel 520 or Samsung 830 or Samsung 840 or Samsung 840 Pro.

People spend $2500 on Mac computers that come with sh*tty graphics and CPU.Spend half of that money on PC and you will get a total beast.

If you want to be 99.99% protected from viruses then pay $30 and buy Kaspersky Internet Security and pay $30 and buy SandBoxie software.These two things alone are enough for you to forget about viruses.

Some tips on what to buy:

At least 4GB RAM. I recommend 6GB if you do gaming and 8GB if you to photoshop.

At least 3rd generation i5 or i7 CPU if you do video/audio editing.Otherwise a 2nd generation i3/i5/i7 will be fine.

Solid State Drive instead of HDD(written above).

At least 250GB hard drive.

Buy a 1TB backup drive and backup your files in there just in case.

Nvidia Graphics Card.

Macs rarely crash and usually stay fast for a long time, but they're very expensive and very proprietary (it's very difficult to repair or upgrade them without Apple getting mad at you). There aren't as many viruses for Mac as there are for PC.

You can specify the amount of time that passes on any Windows or Mac laptop by going into the power settings.

A Macbook Pro and a Samsung Series 7 (An example PC) have almost the exact same hardware but the Macbook pro is about $1,000 more.

You could go for either. I personally prefer PC but it seems your needs are best met by a Mac. If you're on a budget then definitely get a PC.

MacBook Pro if u want an laptop if u want desktop then go for the new iMac :)