No, it's not possible. Only UberMods can freeze the accounts BUT while freezing the account, he/she will have to give a reason for that, which is obviously a reaction to the atrocious acts done by the malefactor like creating duplicate accounts, using explicit pics, posting antagonistic/offensive things, harassment or unwanted private messages or spam etc.
In that case, if you want to take a break, you don't need to do anything. Just leave your account as it is and you can reclaim it later whenever you want. No matter how long your hiatus is, your account will always remain conserved. Remember: You will lose your xper points by the rate of No login for 7 days -20 No login for 30 days -50 No login for 90 days -100
There's no need... your account will always be here, no matter how long of a break you take. Username sitting is usually frowned upon anyways, but yeah, if you're going on a hiatus you don't have to do anything, don't deactivate it, just let your account be and it'll be here just as you left it whenever you return.
Deactivation cannot be undone. Only Uber mods can "freeze" an account, but that is done for very serious reasons and I think typically the admins do it. Just take a break and don't look back for a while. :p
Nope, once it's deactivated, it's deactivated for good requiring a new account. Your best option for taking a break is to set your entire account to privet and just not use it till your read to use it again.