Most fans will argue that WR is the second greatest positional need for the Bears, but in my opinion the two glaring needs on this team are in the trenches at OL and DT. Wide Receiver is a big need, but in terms of the draft it ranks 4th behind CB, DT, and OL, in my opinion. You might find some impact OL or DL in free agency, but the cornerstones guys that will be with your team for 10 to 12 years are found in the draft.
For example Julius Peppers is a impact free agent acquisition, but Clay Matthews is a cornerstone player you can build around for years. In this year's up-coming draft, there are some defensive and offensive line cornerstone caliber players. Wisconsin LT Gabe Carimi and Penn State C Stefen Wisniewski is the type of offensive lineman you can build around; while on the defensive side of the ball Nick Fairley and DaQuan Bowers are cornerstone players that you can insert pieces around.
The question here is what way the Bears should go with their first pick. Here's my case for both lineman positions.
The Case for DT
That dominant Warren Sapp 05-06 Tommie Harris defensive tackle has been missing from this tampa-2 scheme for 3 years now. When making my case for DT you have to look no further than the depth at the position. Guys like Henry Melton and Matt Toeaina are solid rotation guys, but not a long term answer at DT. The Bears need that disruptive defensive tackle to take pressure off of the edge rushers. Julius Peppers and Israel Idonije are very good at getting to the Quarterback, but there have been some games last season where they needed more help (specifically Peppers) from the DT. Just imagine the attention that will be drawn away from a beast pass rusher like Peppers because of the pressure the defense is providing inside at DT. A dominate DE and DT in a tampa-2 defense can really limit what an offense can do. In a division where you will see Aaron Rodgers and Matthew Stafford for many years to come, you need to have a dominate defensive line to contain those guys. Lastly, there's a good chance that the top OT will be taken off the board by the time the draft rolls around #29. You don't want to settle for a prospect like Marvin Austin who resembles your 2008 DT pick Marcus Harrison.
The Case for OL
When the Bears acquired Jay Cutler on April 2, 2009, they got one of the most physically gifted QB's in the league. In two off-seasons, Jerry Angelo hasn't done squat to accommodate his QB with valuable resources specifically offensive line. In Cutler two year's in Chicago, he has been sacked 87 times. This team has been long overdue for an overhaul at offensive line, and if this team wants to catch up with Green Bay they have do a better job building pieces around Jay Cutler starting with the offensive line. The case for selecting OL with the first pick is that even if one of top 4 OT doesn't fall to #29, there are still valuable interior linemen that will be available. Guys like Florida OG Mike Pouncey, Villanova OG Ben Ijalana, and Penn State C Stefen Wisenski will be available. If you want that top OT you can take extreme measures for example using your 1st and TE Greg Olsen to move up.
If you ask me, I would rather start building around your investment, which means building a dominate offensive line so your QB won't turn into the next Marc Bulger. Which ever way they go I won't have a problem with it because the positions are both glaring holes on the team.