Honestly, I can play with anything. It all depends on the situation.
What I will normally use on real maps, are ak/m4/scout. Even on awp/auto allowing servers, I opt for the scout instead to snipe. Much faster, and lighter so I can carry it. Easier to noscope too. I only really play jail and highschool now. As a CT on highschool I normally scout. M4 if my team is getting dominated and we need firepower, since I'm able to take lots of T's down with it. It's fun. The spray/pulse is also very easy to control. Sometimes I'll use para/p90 if I need to spam somewhere.
As a T, I'll also snipe, since there are good vantage points (I rarely use window, on either team, however). I like the AK because it only takes one shot to the head to take them out, and I'm able to aim that. You can see me running around with an m3 as well, especially if I'm coming down T stairs. My secondary on either team is almost always deagle. At times, p228.
Other guns I will use soon enough to work on my FBG achievements.
On jail, as a CT I like using the m4, simply because it matches the profile of a prison guard. I will sometimes opt for the snipers (in jail I WILL use awp, because sometimes it is needed). I like using shotties there too. I rarely ever will use an AK in jail.
I will use aug/sig as well, but prefer m4/ak more, even for long-range shots.