EvE online requires a massive investment of time. It is large and deep and open ended. Do you like mining asteroids? I am very concerned at CCP's technical ability to deliver a safe product though. They seem to have lost the plot technically IMHO.Recently there have been reports that the game somehow trashed some people's hard drive. I haven't gone into that very deeply. However, I used to play with three accounts running simultaneously on the same machine. Many people do this. Then the fools brought out a patch (some nonsense about vista compatibility) which mixed up all the user settings and user information in one directory. This was some time ago now (6 months?) but I gave up at that point out of sheer disgust. If a company doesn't understand its user base and brings out patches which break the end user's config then they don't deserve business and the massive investment of time such an MMO needs. If you only have two months I'd forget EvE frankly. You will barely scratch the surface. You need a year or more.
LOTRO - I loved it up till about level mid thirties when the sheer hassle of finding people to group with for the quest chains (not really optional) drove me away. Its like WoW only cuter, smaller. And not so refined. Kept my interest for about three months with multiple characters up to mid twenties and thirties in level. Don't fall for the lifetime subscription - you'll not get the benefit.
SOE offerings - avoid. Especially Vanguard. SOE are crap and annoy the hell out of me. Sorry SOE.
Many people reckon that Guild Wars is a stonking game - I've not played it much so can't comment.
WoW. I started playing WoW just before Xmas. The last time I played WoW was in the retail Beta and for about 8 months after retail release. Was it 2004? I have to say the game is much as I remember, but lots of things that used to annoy me (timesinks and enforced grouping to progress) are now no longer there. The graphics struck me as a bit crude for the first few minutes of playing but that quickly passed. I strongly recomend WoW as a 2 month fix for the following reasons. Firstly its very slick, mature, tuned and stable. Secondly, they have changed the game for obvious reasons tied up with getting people to the level 60+ expansion, so that is entirely possible to solo the whole thing to lvl 60, if you are ok about avoiding instances. What I am saying here is that WoW is now playable as a monumentally complex, varied and replayable single player RPG with an optional input from other players in chat, auction house etc. I'll stress that - no messing about getting groups together to progress unless you want to! More stressing - all quests seem to be soloable except those which end up in an instance. Third it is cheap and you don't even need a credit card. Fourth, Levelling has been speeded up dramatically I will get to LvL 60 just on Kalimdor. I can use the other continent for a whole new character. Finally, I haven't got to the new expansion stuff yet, but I'm level 52 in a month or so of play without being a power leveller. I am on Steamwheedle Cartel RP PVE server - its not a radical RP server, just people who take their gaming a bit seriously. All the little loud mouthed, argumentative, foul mouthed, noisy, excitable, big egos seem to be on other servers. I am surprised to be having so much fun having rejoined the evil blizz empire. The only downside I can report is constant spamming in local chat by gold sellers when you are in one of the big towns.
If your decision is coming down to a single player RPG or an MMO go with WoW, get the best of both worlds, and ignore the pathetic inverse snobbery so prevalent even here.
But if you know, you know.